Frequently Asked Questions (FAQs)
contributed by Thomas Narten
Welcome to the wonderful world of aquariums. This FAQ provides
advice
and guidance to help insure success in your endeavor. Though this
document is designed for a first _freshwater_ aquarium (saltwater
people: make sure to read the SALTWATER BEGINNER FAQ), there is
much
information applicable to both freshwater and saltwater aquaria.
This FAQ is a work in progress; if there is anything you feel we've
left out, please drop a suggestion to the author or the FAQ Working
Group, and we'll see if we can add it in on the next release. The
FAQ
Team
Table Of Contents
Before You Buy...
* Introduction
+ Tips to Insure A
Successful First Aquarium
+ How Much Time and
Effort Is Involved?
* Tank and Equipment
+ Where to Get It
+ What Is Essential
(Tank,
Heater, Thermometer, Filter, Gravel, Light and Hood,
Powerhead or
Airpump, Stand, Cleaning Tools, Bucket, Nets,
and Test
Kits)
* How to Find a Good Aquarium Store
Setting Up Your Tank...
* Preparing Your Water
+ Tap Water
(Chlorine,
Chloramine, Other Chemicals)
+ Well Water
* ``Cycling'' Your Tank
+ The Nitrogen Cycle
+ How Much Ammonia Is Too
Much
+ Minimizing
Cycling-Related Stress
+ Speeding Up the Cycling
Process
* Practical Freshwater Chemistry
+ The Big Components:
(pH,
Buffering Capacity, General Hardness, Salinity,
Nutrients and
Trace Elements)
+ Altering Your Tank
Water's Chemistry
(Hardening,
Softening, Changing pH)
* Which Test Kits are Important
+ Ammonia (yes)
+ Nitrate (maybe)
+ Nitrate (yes)
+ pH (yes)
+ General Hardness
(maybe)
+ Buffering Capacity/KH
(maybe)
Setting Up Your Fish...
* Fish Stress
+ The Meaning of Fish
Stress
+ Causes of Fish Stress
+ Symptoms of Stressed
Fish
* Adding Fish
+ What's a Good Kind of
Fish
+ How Many Fish Can one
Keep
+ Acclimating New Fish
+ What and How Much to
Feed
* Partial Water Changes
+ Purpose
+ How Often
* Long-term Success
+ Coping with Algae
+ Coping with Snails
+ Coping with Vacations
+ Coping with Moving
+ Euthanizing Fish
+ Breeding Fish
BEGINNER FAQ: INTRODUCTION
What constitutes success? Healthy fish that live a long time, quite
likely even breeding and having babies. Success also means having a
tank that looks nice without a lot of maintenance (e.g., constantly
battling excessive algae growth).
How To Insure Your First Aquarium Is a Success
Having a successful tank is not difficult, nor is it necessarily a
lot
of work, provided you use some common sense. These guidelines are
based partly on science and partly on experience gleaned from
aquarists having many years experience in ``the art of fishkeeping.''
The following list summarizes the most important rules for success.
Each is discussed in more detail in subsequent sections of this
document.
Have patience.
Buying a tank, setting it up and filling it with fish all in the
same
day, while possible, is a sure road to disaster. In fact, setting
up
and fully stocking your first tank will take close to two months!
An ounce of prevention is worth a pound of cure.
Providing an environment that minimizes fish stress is the key to
success. As fish become stressed, their immune systems weaken and
they
become more susceptible to disease. Moreover, most fish medicines
don't work very well, aren't worth the money, and frequently do
more
damage than good. Often, the best treatment for sick fish is to
relieve stress by
1. performing regular partial water changes,
2. not overfeeding,
3. checking that your filtration system works,
4. giving them enough room to live, and
5. keeping them with compatible tank mates.
(See the STRESS SECTION of this FAQ for full details.)
Understand and respect the nitrogen cycle.
Fish produce toxic wastes (ammonia) that must be broken down by
bacteria through biological filtration. Most fish deaths for
first-time tank owners are a direct result of not understanding the
nitrogen cycle and are completely avoidable. (The NITROGEN CYCLE
SECTION explains how the process works.)
Perform regular maintenance on your filter to keep it clean.
Dirty (clogged) filters operate at reduced efficiency. In the case
of
biological filtration, a clogged filter will be unable to remove
ammonia properly, resulting in fish stress and eventually death.
Floss-based biological filters are cleaned by gently rinsing them
in
used tank water that has been siphoned into a bucket. Undergravel
filters are cleaned through regular vacuuming. (Filters are
discussed
briefly in this beginner FAQ, and in more detail in their own
FILTRATION FAQ.)
Properly treat all tap water before adding it to your tank.
Municipal water contains such added chemicals as chlorine or
chloramine to make it safe for human consumption. These substances
are
toxic to fish and can weaken, damage or even kill fish. (See the
WATER
TREATMENT section of this FAQ for details.)
Take the time to learn basic water chemistry
Basic water chemistry is pH, hardness and buffering. You needn't
enroll in a chemistry course, but you should know enough about
water
chemistry and the specifics of your local water supply so that you
can
keep fish happy. Every location's water source is different, and
some
fish won't be able to survive in your water. You can learn details
about your water from a local fish store, through the use of test
kits, and from local aquarium clubs (or, amazingly, from the
CHEMISTRY section of this FAQ).
Keep the pH of your tank's water stable.
Rapid pH changes stress fish. Tank water has a natural tendency to
become acidic due to the production of nitric acid (nitrates) from
the
nitrogen cycle. Keeping pH stable requires having adequate
``buffering''. If your water is soft, you may need to add buffering
agents. Again, see the CHEMISTRY section for details.
Avoid adding chemicals that lower the pH (e.g. ``pH-Down'').
Such chemicals frequently have undesirable side-effects (e.g.,
stimulate algae growth). Moreover, in most cases (despite what
books
and stores tell you) the pH of water _DOES NOT_ need to be adjusted
to
make it ``more perfect'' for a particular species of fish. If the
pH
of your tap water is between 6.5 and 7.5, it is just fine for most
fish. (This is discussed in the CHEMISTRY section too!)
Pick fish for your water.
Select fish who are native to waters having a similar chemical
properties (pH and GH) to your local tap water. If you have hard
water, choose hard water fish. If you have soft water, choose soft
water fish. This is especially important if you water is outside
the
6.5-7.5 pH range. Changing the natural hardness (or pH) of your tap
water can be hard work and often takes the fun out of keeping
aquariums. Moreover, bungled attempts at adjustment are common and
often worse for fish than the original sub-optimal water
conditions. A
good way to learn which fish live happily in your local water is to
check with a local fish store (or club).
Choose the fish to fit your tank.
Select fish that are compatible with each other and think
long-term.
That 1 inch fish sure looks cute at a store. But what will you do
when
it gets 6 inches long and views its cohabitants as potential meals?
Fish have specific minimal space requirements that are dependent on
their physical size and temperament. Select fish whose needs will
be
met in your tank. Be sure your tank has adequate hiding places
(e.g.,
rocks, plants, driftwood, etc.) for its inhabitants.
Properly acclimate fish before adding them them to your tank.
(Details are covered in the section on ADDING FISH.) _NEVER_ add
store
water to your tank (it may contain diseases), and if feasible,
quarantine new purchases for 2-3 weeks before adding them to your
tank.
Perform regular partial water changes.
Changing 25% of your tank's water every other week serves two
purposes: it dilutes and removes nitrate before it accumulates to
dangerous levels, and it replaces trace elements and buffers that
get
used up by bacteria, plants, etc. Finally, regular partial water
changes help insure that your tank's water chemistry doesn't
deviate
significantly from that of your tap water. The latter benefit is
especially important should disease strike your tank; water changes
are the most important step in controlling disease, and large water
changes are not safe unless the chemical composition (e.g., pH and
GH)
of your tank's water is similar to your tap water.
Shop only at ``reputable'' stores.
Sadly, many pet stores are more interested in taking your money
than
selling you healthy fish. It is almost always worth spending a
little
more money to get quality fish. Diseases introduced to your tank
with
newly purchase fish may infect your other fish with catastrophic
results. Buying a low cost fish is also not much of a bargain if it
dies less than a month later. But many stores will instead try to
sell
you equipment and medications you don't really need. Your best
defense
is to arm yourself with knowledge so that you can properly evaluate
their advice. Some hints for finding ``reputable'' stores can be
found
in the STORES SECTION.
The above summary serves as a reminder of the principles that lead
to
happy fish keeping. Each of these topics (and many more) is
discussed
in the remainder of this document.
How much time and effort is involved in keeping a fish tank?
For a 10-20g tank, once it is set up, expect to spend about 30
minutes
every other week doing partial water changes, cleaning the tank,
etc.
If this is too much time for you, _DON'T GET INTO THIS HOBBY!_ You
will also spend a few minutes once or twice a day feeding your
fish,
turning the lights on and off, etc. Warning: many people spend much
more time than this simply looking at their tank and its
inhabitants.
Of course, that is the whole point. :-)
Be prepared to spend several hours researching the hobby before you
make your first purchase. The more time you spend _BEFORE_ you
actually get the tank, the smoother things will go. Go to several
pet
stores to find one that looks like a reputable place. Visit them
again
several more times. Get some beginner books. Read this beginner FAQ
several times.
Most people who get frustrated with fish tanks made mistakes that
could have been easily avoided. The way to avoid mistakes is to
learn
the basics (e.g., the nitrogen cycle) BEFORE you put fish in your
tank. There are few things more upsetting than frantically reading
the
FAQ for the first time, while three feet away your beloved fish are
dying. Remember: most aquarium problems are easy to prevent, but
hard
to deal with after the fact.
NEXT: Tank and Equipment
UP: Contents
BEGINNER FAQ: EQUIPMENT
Where To Get Your Equipment
All fish stores sell tank setups containing ``everything you need''
for one price. However, a smart shopper looks carefully at what the
package contains to be sure it includes only what you need (and
doesn't include things you don't). Packages vary from store to
store,
some are more appropriate than others. Be especially wary of setups
bought at discount stores (e.g., ``Hartz'' brand). They often
include
obsolete technology, noisy pumps, cheap heaters, etc.
Garage sales are a great way to get into the hobby cheaply.
However, a
few cautions are in order. Before buying the tank, examine it
closely
for cracks or scratches. Although cracks can be fixed, doing so is
more hassle (for a beginner) than it is worth. Don't buy a
scratched
tank; algae will grow in the scratches making the tank look bad. Be
wary of really old equipment. It may no longer work well.
Before setting up the tank (especially if the tank is used), check
it
for leaks. Fill it with water outside and leave it for a week. A
leak
on your carport is a lot less of a problem than one in your living
room.
To clean the tank, _NEVER_ use soaps or detergents. Use water and
nothing else. If you want to sterilize the tank, gravel, etc. wash
everything plastic in a mild bleach solution (use pure bleach, not
one
with other additives). Rinse everything well in clean water, and
let
everything soak a bit in a solution with a bit of added
dechlorinator.
(Non-plastic) gravel can be sterilized through boiling.
Equipment: What's Essential and What's Not
Tons of aquarium gadgets are available at pet stores. Some are
essential, others are useful only for specialized applications, and
some are completely useless (though stores selling them probably
won't
tell you that). The following checklist shows the items that will
likely to be of use to you.
Tanks
Tanks come in many shapes and sizes, but there are only two types:
glass and acrylic. You will probably want to get a glass tank. In
summary:
Glass
Acrylic
=====
=======
cheapest per gallon
more expensive per gallon
hard to scratch
scratches easily (e.g. scraping algae
with razor blade)
scratches permanent
scratches can be buffed out (though
not easily)
higher index of refraction lower IOR (tank
distorts less when
viewed from angle)
empty tank heavy
same sized tank weighs less (empty)
(important with tanks >30g)
Tank stand only needs to Special stand
needed that supports
support edges
entire base of tank (not just edges)
more easily broken
harder to break
The size and shape of the tank is completely up to you. However,
keep
the following in mind:
1. Contrary to first impressions, larger tanks are not
necessarily
more work than smaller ones (within
reason). In particular, it is
easier to keep water chemistry stable in
larger tanks than in
smaller ones (the less water, the more
easily a small chemical
change causes a big change in relative
concentration).
Much of the regular maintenance work does
not require twice the
time for twice the size. For example, a
regular partial water
change for a larger tank may require one
more bucket of water than
for a small tank. That doesn't translate
into twice the work,
since you already have the bucket and
siphon ready, your hands are
already wet, etc.
2. It is very common for people to really like their fish
tank and
want to add more fish. A larger tank can
hold more fish safely.
Indeed, a single 10g tank adequately
supports only a handful of
medium sized fish.
3. Note, however, that the number of fish that a tank can
safely hold
depends not only on the volume of the tank,
but on its shape. For
example, some fish spend their entire lives
near the bottom.
Doubling the volume of a tank by doubling
its height won't allow
you to keep more bottom dwelling fish.
Surface area is more
important than volume in determining how
many fish a tank can
support.
If possible, start with at 20g (or larger) rather than a 10g (or
smaller). A 20g (``high'' or ``tall'') makes an excellent first
tank
size. Avoid all tanks smaller than 10g. They are simply too small
to
keep healthy. For example, although many stores sell them, the tiny
1
gallon goldfish bowls are totally inadequate for even a single
fish.
Stay away from them!
Heaters
If you are keeping tropical fish, you will need a heater. A heater
insures that a tank doesn't get too cool, and that the temperature
stays steady during the course of the day, even when the room cools
off (e.g., at night). For many tropical fish, a temperature of 78F
is
ideal.
There are two main heater types. Submersible heaters stay
completely
below the water. A second, more traditional style, has a partially
submerged glass tube (which contains the heating coils), but leaves
the controls above the water. Submersible heaters are the better
design, as they can be placed horizontally along the tank's bottom.
This helps keep tank temperature uniform (heat rises), and prevents
the heater from becoming exposed while doing partial water changes.
With the traditional design, one must remember to unplug the heater
before doing water changes; if the heater is accidentally left on
while the coil is above the water, the tube gets hot and may crack
when you fill the tank back up with water.
If your room is never more than 8-10F degrees cooler than your
target
tank temperature, a heater of roughly 2.5 Watts per gallon will
suffice. If the differential is higher, up to 5 Watts (or more) per
gallon may be necessary. Remember, the heater needs to keep the
tank
at its target temperature, even when the room is at its coldest
point;
the tank's temperature should not fluctuate.
Heaters (especially cheap ones) will fail. Most often the contact
that
actually turns the heater on and off gets permanently stuck, either
in
the on or off position. In the former case, your tank can get
_VERY_
hot, especially if the heater is larger than your tank actually
requires. To minimize potential problems, avoid heaters larger than
the optimal size for your tank. To prevent winter disasters, use
two
smaller heaters in parallel rather than one large one. That way if
one
fails, the consequences won't be as disastrous.
Thermometers
You will need a thermometer to verify that your tank stays at its
proper temperature. Two types are commonly available. The
traditional
bulb thermometer works the same way as the ones you can buy for
your
house. They either hang from the top edge of your tank, or float
along
the surface. The second common design is a flat model that sticks
to
the outside of the glass. In this design, liquid crystals activate
at
a specific temperature, either highlighting the numerical
temperature
or a bar that slides along a scale.
Aquarium thermometers can be rather unreliable (check out the ones
on
display at a fish store --- they should all register the same
temperature, but frequently don't). Thus, thermometers are good for
verifying that your temperature is not too far off, but may be off
by
several degrees in some cases. When buying a thermometer, look at
all
the thermometers and pick one that has an ``average'' temperature,
rather than one of the extremes.
Filters
There are three types of filtration: biological, mechanical and
chemical. Biological filtration decomposes the toxic ammonia that
fish
produce as waste products. All fish tanks _MUST_ have biological
filtration; biological filtration is the cheapest, most efficient
and
most stable way to breakdown toxic ammonia. Mechanical filtration
traps such particles as plant leaves, uneaten food, etc.
(collectively
known as mulm), allowing them to be removed from the tank before
they
decompose into ammonia. Chemical filtration (e.g., activated
carbon,
zeolite, etc.) can remove (under limited circumstances) such
substances as ammonia, heavy metals, dissolved organics, etc.
through
chemistry (e.g., ``adsorbtion'' or ``ion-exchange resins'').
Chemical
filtration is mostly useful for dealing with short-term problems,
such
as removing medications after they've served their purpose, or
purifying tap water before it goes into a tank. A healthy tank
_DOES
NOT_ require the use of chemical filters such as activated carbon.
One point about filtration cannot be made enough. _ALL FISH TANKS
MUST
HAVE BIOLOGICAL FILTRATION._ Although chemical filtration can
remove
ammonia under limited circumstances, it are _NOT_ a general
solution.
Typical filters perform some or all of the three filtration types
in
series. Mechanical filtration (if present) usually comes first
(where
it is called a ``pre-filter''), trapping particles that might clog
remaining stages. Biological usually comes next, followed by the
chemical filtration section (if present). Whether or not chemical
filtration is useful (or even helpful) depends on who you talk to.
It
can be useful for removing fish medicines after their effectiveness
has ended (partial water changes do the same thing though). They
can
also remove trace elements necessary for plant growth (with obvious
results). Unless you have a good reason to believe that your
circumstances require chemical filtration, avoid it.
Filters are not maintenance-free. For example, if debris is allowed
to
accumulate in a mechanical filter, it decomposes into ammonia,
negating its primary purpose. Likewise, a biological filter's
effectiveness diminishes as it becomes clogged. Biological
filtration
requires water movement across a large surface area on which
bacteria
have attached (e.g., floss or gravel). The less surface area
available, the less effective the filter. UGFs are cleaned by
regularly vacuuming the gravel (e.g. while doing partial water
changes). Canister and power filters are cleaned by removing the
media
and gently squeezing it in a bucket of used tank water (tap water
may
contain bacteria-killing chlorine).
There is no magic formula for what size filter one needs. Consult
with
specific manufacturer's ratings and be conservative. You can't have
too much filtering (though you can have too much water movement),
so
err on the side of overfiltering. Filters are discussed in more
detail
in a separate FILTER FAQ.
Gravel
Gravel serves three main purposes. First, it serves as decoration,
making your tank look nicer. Second, if using an UGF, gravel is
mandatory as it _is_ the filter media (the surface area on which
bacteria attach). Third, in plant tanks, it serves as a
``substrate''
(e.g. dirt) for plant roots (consult the PLANT FAQ for details on
what
quantity and type of substrate is appropriate for plants).
Ultimately,
the choice of color, size, etc. is up to you. However, be aware
that
dark gravel better highlights a fish's colors. Fish adjust their
colors to match that of the surroundings, and light gravel tends to
wash out a fish's true colors.
Most of the gravel sold for aquariums is plastic coated. For
obvious
reasons, you should not boil it. :-) It is also very expensive ($1
a
pound). Gravel can be purchased for much less at patio stores
(e.g.,
Wallmart, Home Quarters, local sand and gravel suppliers, etc.).
However, it often tends to be larger than ideal and too light in
color
(e.g., marble chips). Sand can also be used.
Be aware that not all gravel is inert. For example, coral, sea
shells,
dolomite and limestone will release (leach) carbonates into the
tank
raising its pH buffering capacity (see the CHEMISTRY SECTION for
details). When keeping African rift lake cichlids, this is
desirable.
But in most other cases, you will not want your gravel affecting
the
water chemistry. As a quick test, drip an acid (e.g., vinegar) onto
the gravel in question. If it foams or bubbles, the gravel is going
to
leach carbonates into the water. To be absolutely sure, fill a
bucket
of gravel with water and measure the pH over a period of a week. If
the pH remains stable, it should be safe to use in your tank.
When used for the first time, gravel should be washed thoroughly.
Simply rinse clean water through it until the water comes out clear
(tap water is fine). For example, put the gravel in a bucket of
water,
fill it with water, and churn the gravel up. Drain the water and
repeat the procedure until the water remains clear. Before using
gravel of unknown origin (e.g., not purchased at a fish store), you
may (as a precaution) want to boil it for 15 minutes to kill
unwanted
bacteria.
Driftwood and other Decorations
It is safe to place items in your tank as long as they are inert,
meaning they won't release (leach) chemicals into the water. Most
plastics are inert inert, as are glass and ceramic.
Wood may leach substances into the water, changing the pH in a
possibly inappropriate manner. Driftwood often leaches tannins and
other humic acids into the water (much like peat moss), possibly
softening it and lowering its pH. The water may also obtain a
yellowish tea-colored tint. The tint is not harmful and can be
removed
by filtering the water through activated charcoal.
If you use wood that you've found yourself (e.g., woods or lake),
boil
it first to kill any pathogens. Boiling it (long enough) will also
make it sink.
Lights & Hood
You will probably want to purchase lights and a hood. A hood
prevents
fish from jumping out of the tank and reduces the rate at which
water
evaporates. A good hood effectively seals the tank (except perhaps
where the heater and filter reside). You want as little water as
possible evaporating as it may raise the room's humidity to
unacceptable levels and requires more maintenance (i.e., you will
have
to ``top off'' the tank once or twice a week to replace the lost
water).
There are two styles of hoods. Full hoods combine the light and
hood
as a single unit. Hoods include space for only 1 or 2 (parallel)
fluorescent light tubes, which is fine for fish-only tanks, but not
usually enough for growing plants. Glass ``canopies'' cover the
tank
with two strips of glass connected by a plastic hinge, but don't
include lighting. A separate strip (or other) light is used in
conjunction with it. Canopies are a bit better for plant tanks than
full hoods; one can upgrade or change the lighting without
replacing
the entire hood, and in situations where very high wattage is
needed,
one can usually fit more light bulbs directly above the tank.
Light serves two purposes. It highlights and shows off your fish's
colors and provides (critical) energy for plants (if present).
Unfortunately, the two purposes conflict somewhat. In a fish-only
tank, a single low-wattage fluorescent bulb suffices and does a
good
job of showing a fish's true colors (most fish don't like bright
lights either). If you want to grow plants, however, more light is
needed, and the bulb's spectrum becomes an issue; be sure to
consult
the lighting sections in the PLANT FAQ before purchasing your light
and hood setup.
Whether or not you will be growing plants, fluorescent lights are
the
way to go. Incandescent bulbs give off too much heat, causing your
tank to overheat in the summer. Fluorescent bulbs run cooler and
use
less electricity for the same amount of light. Note that in the
summer
time, even fluorescent lighting can produce enough heat to lead to
tank overheating problems, if your house gets warm (e.g, you live
in
the tropics and don't have air conditioning).
Unfortunately, light grows not only plants, but algae. If your tank
contains lots of the kind of light plants desire, and there are no
plants, algae quickly fills the void. Thus, the ideal lighting for
fish-only tanks differs significantly from that for a plant tank.
Two
components of light are of particular importance: intensity (i.e.,
wattage) and spectrum. Plants require intense light and certain
spectral ranges produce more growth than others.
Different types of bulbs give off light in different spectral
regions.
So-called ``full-spectrum'' bulbs attempt to reproduce the sun's
full
spectral range. They are good both for growing plants and bringing
out
a fish's natural colors. Specialized ``plant'' bulbs (e.g., gro-lux,
etc.) emphasize a spectral range that stimulates plant growth. Such
bulbs grow plants (and algae!) well, but fish don't look quite
right
under them, because the light does not have the spectrum of normal
sunlight. The common ``cool white'' bulbs give off light designed
for
humans in windowless offices; they neither grow plants particularly
well, nor bring out a fish's natural colors. As a quick rule of
thumb,
2-4 watts/gallon of full-spectrum (or specialized ``plant'')
lighting
is good for plants; for fish-only tanks, use less than 1
watt/gallon,
and avoid using plant bulbs.
Powerheads
A powerhead is a water pump that runs completely submerged in a
tank.
They typically attach to the ``lift tubes'' associated with UGF
filters, pulling water through the lift tube. The stream of
outgoing
water can usually be oriented in (almost) any direction, and it is
common to point them in such a way that water circulates throughout
the tank and stirs up or ``agitates'' the surface a bit.
Air Pumps
An air pump simply bubbles air through your tank. Air pumps serve
two
purposes. First, they insure that your tank maintains an adequate
concentration of oxygen. An air pump is _NOT_ required for this
purpose, as long as your tank maintains adequate water movement
together with surface agitation. This is generally the case if
external (e.g., box or cannister) filters are used. Second, air
pumps
can be used to force water through a filter (e.g., sponge or corner
filter). If using a UGF, for example, an air pump produces bubbles
that force water up the uplift tubes, pulling water through the
filter. In larger tanks, powerheads perform the same function.
Thus,
an air pump is not required, provided your tank has good water
circulation.
Stands
You will need some sort of stand on which to place your tank. The
stand can either be specially designed to hold your tank, or
existing
furniture. The first thing to consider is whether your chosen stand
can support the tank's weight. When full of water, tanks weigh a
_LOT_
(the water alone weighs roughly 10 lbs/gallon). Consult THE TABLES
in
the BEGINNER FAQ for detailed specs on common aquarium sizes.
If you live in an older or cheaply constructed home, give
consideration to how weight is distributed among the stand's
supports.
The larger the surface area of the leg stands, the less
instantaneous
pressure (per square inch) on the floor. You don't want the stand
to
crash through your floor! If you plan to have a large tank (e.g.,
55g
or more), be sure the floor itself can properly support the weight.
For big tanks, try to place the tank perpendicular to the floor
joists
(so that the weight is distributed over multiple joists). Placing
your
tank near a load bearing wall is also safer than placing in the
middle
of your floor.
Stands should keep the tank level, in order to keep weight
distributed
properly. An un-level tank places stress in the wrong places,
increasing the odds of having the tank break (yes, this does
actually
happen sometimes). In order to more evenly distribute weight on the
stand, it is a good idea to place a 1/4 inch sheet of Styrofoam
between the stand and the tank.
Plants
There are two kinds of plants (depending on who you talk to): real
and
plastic. Both kinds provide decoration and hiding places for fish.
Plastic plants are (obviously) easier to maintain. Although it is
possible to grow real plants in an aquarium, it is not always
trivial
to do so (e.g., plants have special lighting requirements). If you
are
at all interested in trying to grow real plants, consult the PLANT
FAQ
before purchasing your tank --- especially the hood.
Miscellaneous Cleaning Tools
Siphoning is the easiest way to remove water from a tank. For large
tanks, using a ``water python'' or other long hose allows one to
dispense with the bucket and siphon water directly into a drain or
outside garden. When removing water via siphoning, you should also
clean (``vacuum'') your gravel. Many ``water changing'' hoses are
available at local fish stores and include a gravel cleaning
attachment. The basic idea behind them is to connect a wide mouthed
tube to the end of the siphon hose. When the tube is plunged into
the
gravel, the water flow churns up the gravel, but only the detritus
(dirt, mulm, etc) is light enough to be siphoned out. Note that the
dirty water being removed from your tank contains nitrates, which
make
an excellent fertilizer for your flower or vegetable garden.
To remove algae from the side of your tank, a plastic, non-soapy
scouring pad can be used. If you have an acrylic tank, be
especially
careful that the pad isn't hard enough to scratch the side. Many
types
of algae can be wiped free using the floss inserts made for Whisper
filters (cheap and can't scratch).
Some of the slower growing algae simply can't be removed with a
scouring pad without a lot of work (and churning of the tank!). A
razor blade works best at this point. Go to your local fish store
and
purchase a scraper that has a long (foot long) handle with a razor
blade on one end. A razor blade can be used to remove just about
anything from the sides of a tank. However, razor blades _CAN_
scratch
glass, if one is not careful.
So-called ``magnet cleaners'' can also be helpful for removing
algae.
A scraping block on the inside of the tank is held in place by a
magnet held on the outside of the tank. Moving the outside magnet
moves the scraping block, removing algae without having to plunge
your
entire arm in the tank. The best magnet cleaners are those with a
strong magnetic field (e.g., larger magnets), and they work best on
smaller tanks, which have thinner glass.
A toothbrush is one of the most effective tools for removing algae
from the inside of plastic tubing.
Bucket For Water Changes
You will need at least one bucket for adding and removing water
from
your tank. Use the largest bucket you can comfortably work with
(e.g.,
up to 5 gallons). Use it only for your aquarium and don't ever put
any
chemicals in it.
Nets
You will need at least one fish net, and having two is better;
catching fish is easier if you use one net to chase fish into the
other. Nets with a fine mesh are harder to use because of their
high
water resistance. The right net size will of course depend on the
size
of your fish.
Note: netting fish is stressful. In particular, the fish net
scrapes
off some of a fish's protective slime coating. If possible, when
catching fish, use a net to chase the fish into a small plastic or
glass jar.
Test Kits
You will probably want to buy some test kits for measuring things
like
ammonia concentrations. Because there are so many kits,
recommendations as to which to buy are given in a separate TEST KIT
SECTION of this FAQ.
NEXT: Finding a Good Fish Store
UP: Contents
BEGINNER FAQ: FINDING REPUTABLE FISH STORES
Like all businesses, fish stores have to make money to survive.
Unfortunately, some are more interested in profits than selling you
just what you need and nothing more. Consequently, a smart customer
is
a careful shopper.
Of course no store is 100% perfect all the time, but the difference
between a good store and poor one can be astonishing once you've
been
to a few. Visit a store several times, and don't rely on just one
experience. If the same bad patterns are present on multiple
visits,
find another store.
The following highlights some of the things that distinguish a
good,
reputable store from one you should avoid.
If the fish don't look good at the store, chances are they won't
survive long after you bring them home; they may already have been
stressed beyond the point of recovery.
1. A store's fish tanks should be clean and the fish should
look
healthy and unstressed (e.g., no nipped
fins, good colors, fish
active, etc.). Are dead fish removed
quickly? All stores will have
fish die in their tanks; good stores will
remove them quickly
(fish covered with fungus have probably
been dead a long time).
2. Do any of the fish show signs of disease such as ick (tiny
white
spots)? A good store won't sell you _ANY_
fish from a tank that
has ick, even if the specific fish you are
purchasing looks OK.
3. Are incompatible fish kept in the same tank? If so, how
can you
trust the advice they give you concerning
compatible inhabitants
for your tank?
4. Check out the store's policy on fish returns. A good store
will
give you full credit on fish deaths for a
period of a few days,
provided you bring in a water sample so
that they can test your
water for ammonia.
5. Are the sales staff knowledgeable about what they are
selling? A
good store will ask you about your tank
(size, inhabitants, etc.)
in order to find out whether a prospective
fish purchase would be
a good addition to your tank. A bad store
will sell you whatever
you want; they'll be happy to sell you more
fish later, after
incompatible inhabitants have killed each
other.
For beginning aquarists, a good store will
take the time to
explain the nitrogen cycle, and advise you
to wait on fish
purchases until your tank has become
established. A bad store will
neglect to mention the nitrogen cycle,
until you return a few days
later wondering wondering why your fish
died (now they can sell
you more fish, and maybe ``nitrification
bacteria'' to go with
it!).
Ask lots of questions. Be wary of vague
answers; they are a sign
that the seller doesn't know the answer
(and isn't willing to find
out), or worse.
Like that tiny oscar fish? A good store
will warn you that oscar
fish get _VERY_ big, and verify that your
tank is big enough and
that none of its inhabitants will get eaten
by the oscar. A bad
store will remain silent.
6. Be wary of adding medications to your tank; they
frequently don't
work or are unnecessary. (See the DISEASE
FAQ.) A good store will
first ask about your tank's water quality,
verify that cycling has
completed, etc., and suggest water changes.
They will also
recommend medications only if they can
identify the specific
disease. A ``bad'' store will encourage you
to buy medicine,
without regard to whether the specific
medicine is useful in
combating the specific problem you have. A
good store will ask you
what fish you have in the tank, as some
medications are toxic to
certain species of fish. A bad store will
let you find out the
hard way.
7. As a (very) general rule of thumb, stores that specialize
in
aquariums are better than stores that sell
fish as a sideline. In
the former case, a ``bad'' store won't make
money over the long
haul (they can only sucker customers once
or twice) and will
eventually go out of business. In the
latter case, a store's fish
department may continually lose money, but
remain open because the
rest of the store (e.g, puppy sales) is
making money. Of course,
there are exceptions.
8. Finally, buying fish at the cheapest store isn't
necessarily a
good bargain. A healthy fish is worth
paying extra for. A sick
fish may infect all of your tank's
inhabitants or die shortly
after purchase; some bargain.
Is a pattern becoming clear? A good store is knowledgeable about
the
products they sell and will take the time to be sure the customer
is
making a purchase that they will be happy with in the long term.
They
want your repeat business in the future. A bad store will encourage
(or fail to discourage) you from buying things you don't need.
NEXT: Preparing Water For Your Tank
UP: Contents
BEGINNER FAQ: WATER TREATMENT
Municipal Tap Water in the Aquarium
Most people use tap water in their tanks; it is cheap and easy to
use.
Unfortunately (for aquarists), local water companies add chemicals
to
the water to make it safe to drink (e.g., chlorine or chloramine to
kill bacteria). More recently, concern about water flowing through
older lead pipes has caused some water utilities to add pH-raising
chemicals to the water (because lead dissolves less readily in
alkaline water). Consequently, tap water must be specially treated
before it can safely be used in fish tanks.
Another potential problem concerns variability in the chemical
properties of your water supply over time (e.g., month-to-month).
Some
water districts don't have enough water themselves, forcing them to
purchase additional water from neighboring water districts in times
of
shortages. If this water has a different chemical properties (e.g.,
hardness), your tap water's chemistry will vary as well. As a
common
example, high bacteria levels are more of a problem in summer than
winter, especially in warmer climates. Consequently, it is not
uncommon for water companies to use more chlorine in summer months
to
keep bacteria in check. Even such factors as local weather can have
an
impact; heavy rains may cause the hardness of your water supply to
decrease as local reservoirs fill.
In general, chlorine and chloramine are the two additives that
cause
the most problems. Note that these two substances are _VERY
DIFFERENT_! Be sure you know what is in your tap water and treat
appropriately.
Chlorine
In the US, EPA guidelines require that tap water at any faucet
contain
a minimal chlorine concentration of 0.2 ppm, and stringently limits
the concentration of bacteria (which may require more than 0.2 ppm
chlorine to keep in check). Because chlorine breaks down over time,
the chlorine concentration of the water that comes out of your tap
will be lower than that put in at water plant. Thus, the exact
concentration at your faucet depends on how far you are from the
water
plant, how long it takes the water to travel from the water plant
to
your house, how much chlorine is initially added, etc.
Chlorine at high concentrations is toxic to fish; at lower
concentrations, it stresses fish by damaging their gills.
Concentrations of as little as 0.2-0.3 ppm kill most fish fairly
rapidly. To prevent stress, concentrations as low as 0.003 ppm may
be
required. Fortunately, chlorine can easily be removed from water by
the chemical sodium thiosulfate, readily available at fish stores
under various brands. Sodium thiosulfate neutralizes chlorine
instantly. Note that there are many ``water treatment'' products
that
are advertised as ``making tap water safe''. Read labels carefully.
Inevitably, the ones that neutralize chlorine all contain sodium
thiosulfate, plus other substances that may or may not be useful.
If
your water only contains chlorine (as opposed to chloramine),
sodium
thiosulfate is all you need. The most cost-effective treatments use
only 1 drop per gallon of water. Most other water treatments are
much
more expensive in the long-term; they may require a teaspoon of
treatment (or more) per gallon!
Chlorine is relatively unstable in water, escaping to the
atmosphere
on its own. Water left in a bucket (or tank) with adequate water
circulation (e.g. filter or airstone) will be free of chlorine in
24
hours or less.
Many netters report that they perform partial water changes without
ever treating their tap water to remove chlorine. Keep in mind that
even though fish show no _APPARENT_ ill effects from untreated
water,
that doesn't mean that the chlorine isn't stressing your fish. How
much stress depends on how much chlorine is introduced to the tank,
which depends on many factors (including the percentage of new
water
added). Because chlorine removers are so cheap (pennies per usage),
the insurance they provide should not be passed up.
Chloramine
One problem with using chlorine to treat water is that it breaks
down
relatively quickly. Another concern with the use of chlorine is
that
it can combine with certain organics (that may or may not be
present
in your water) forming trihalomethanes, a family of carcinogens.
Consequently, many water companies have switched from using
chlorine
to using chloramine. Chloramine, a compound containing both
chlorine
and ammonia, is much more stable than chlorine.
Chloramine poses two significant headaches for aquarists. First,
chlorine-neutralizing chemicals such as sodium thiosulfate only
neutralize the chlorine portion of the chloramine, neglecting an
even
bigger problem: deadly ammonia. The consequences can be devastating
to
fish. Although a tank's biological filter will (eventually) convert
the ammonia to nitrate, the time it takes to do so may be longer
than
what your fish can tolerate.
The second problem relates to water changes. One of the primary
reasons for doing regular water changes is to remove nitrates that
build up. If your replacement tap water contains ammonia, you'll be
putting nitrogen right back into your tank and it will be
impossible
to reduce the nitrates below the concentration in your tap water.
Fortunately, tap water concentrations are relatively low (1 or 2
ppm);
you are more likely to have a much higher concentration of nitrate
in
your tank.
Chloramine can be safely neutralized through such products as
Amquel,
which neutralize both the ammonia and chlorine portions of the
chloramine molecules. The neutralized ammonia will still be
converted
to nitrates via a biological filter.
Another method for neutralizing chloramine is to age the water
while
simultaneously performing biological filtration. For example, get
an
appropriately-sized (plastic) garbage can, fill it with tap water,
dechlorinate it with sodium thiosulfate, and then connect an
established biological filter to it. Just as in your tank, the bio
filter will convert the ammonia to nitrate, after which it can
safely
be added to your tank. Note: you must add sodium thiosulfate to
neutralize the chlorine; otherwise, the chloramine will kill the
bacteria in your biological filter.
Alternatively, the ammonia can removed by filtering the water
through
zeolite or carbon before adding it to your tank. [Note: folks
report
mixed success with this. If you have concrete (positive or
negative)
experience to report, please notify the FAQ maintainers.]
Other water impurities you should be aware of
In addition to the additives described above (chlorine and
chloramine), municipal water may (or may not!) contain other
elements
that the aquarist may need to know about. Water in some locations
actually contains nitrates. In some places, water contains elevated
concentrations of phosphates (1 ppm or more). High phosphate has
been
linked to algae problems, and a comprehensive algae control
strategy
may require removing phosphates. High levels of iron (1 ppm or
more)
have also been linked to thread algae. Consult the algae section of
this FAQ for more details.
How to Find out What Your Local Water Company Adds to Your Tapwater
The quick answer is to ask someone who knows. A local fish store
(if
they reside in the same water district as you do) should be able to
tell you. Alternatively, call your local water utility. Ask to
speak
with the ``water chemist''. Tell them you are an aquarist and want
to
know about the pH, GH, and KH of your water, as well as how much
the
water characteristics vary from month to month. Finally, (in the
US)
if you really want details, have them send you a copy of the
periodic
water report they are required to generate for the EPA. It contains
a
detailed listing of exactly what your water contains and in what
concentrations (e.g., iron, nitrates, phosphates, etc.). By law,
the
report is available for public inspection.
Well Water
You may have access to well water instead of municipal tap water.
One
advantage with well water is that you don't need to deal with
chlorine
and chloramine. On the other hand, well water is frequently (much!)
harder than water available through local utilities. In addition,
the
only way to know its composition (GH, KH, etc.) is to run tests on
it
yourself. Alternatively, there are companies to which you can send
water samples that will perform a detailed analysis of its contents
(for $20-100).
One potential problem with using well water is that it frequently
contains high concentrations of dissolved gases (which may be
dangerous to fish). For example, well water is frequently
supersaturated with CO2, which lowers the water's pH. Once the CO2
escapes, the pH will increase. Fish shouldn't be subjected to this
temporary pH fluctuation. For safety, aerate well water thoroughly
for
several hours before adding it to your tank.
NEXT: ``Cycling'' Your Tank
UP: Contents
BEGINNER FAQ: THE
NITROGEN CYCLE, AND ``NEW TANK SYNDROME''
What Is the Nitrogen Cycle?
Like all living creatures, fish give off waste products (pee and
poo).
These nitrogenous waste products break down into ammonia (NH3),
which
is highly toxic to most fishes. In nature, the volume of water per
fish is extremely high, and waste products become diluted to low
concentrations. In aquariums, however, it can take as little as a
few
hours for ammonia concentrations to reach toxic levels.
How much ammonia is too much? The quick answer is: if a test kit is
able to measure it, you've got too much (i.e., it's in a high
enough
concentrations to stress fish). Consider emergency action (water
changes and zeolite clay) to reduce the danger. (A more detailed
discussion of ammonia toxicity can be found later in this section.)
In aquaria-speak, the ``nitrogen cycle'' (more precisely, the
_nitrification_ cycle) is the biological process that converts
ammonia
into other, relatively harmless nitrogen compounds. Fortunately,
several species of bacteria do this conversion for us. In
particular,
_Nitrosomonas_ species (among others) convert ammonia (NH3) to
nitrite
(N02-), while _Nitrobacter_ species (among others) convert nitrite
to
nitrate (NO3-). Thus, cycling the tank refers to the process of
establishing bacterial colonies in the filter bed that convert
ammonia
-> nitrite -> nitrate.
The desired species of nitrifying bacteria are present everywhere
(e.g., in the air). Therefore, once you have an ammonia source in
your
tank, it's only a matter of time before the desired bacteria
establish
a colony in your filter bed. The most common way to do this is to
place one or two (emphasis on _one_ or _two_) hardy and inexpensive
fish in your aquarium. The fish waste contains the ammonia on which
the bacteria live. Don't overfeed them! More food means more
ammonia!
Some suggested species include: common goldfish (for cold water
tanks), zebra danios and barbs for warmer tanks, and damselfishes
in
marine systems. Note: Do not use ``toughies'' or other feeder
fishes.
Although cheap, they are extremely unhealthy and using them may
introduce unwanted diseases to your tank.
During the cycling process, ammonia levels will go up and then
suddenly plummet as the nitrite-forming bacteria take hold. Because
nitrate-forming bacteria don't even begin to appear until nitrite
is
present in significant quantities, nitrite levels skyrocket (as the
built-up ammonia is converted), continuing to rise as the
continually-produced ammonia is converted to nitrite. Once the
nitrate-forming bacteria take hold, nitrite levels fall, nitrate
levels rise, and the tank is fully cycled.
Your tank is fully cycled once nitrates are being produced (and
ammonia and nitrite levels are zero). To determine when the cycle
has
completed, buy appropriate test kits (see the TEST KIT section) and
measure the levels yourself, or bring water samples to your fish
store
and let them perform the test for you (perhaps for a small fee).
The
cycling process normally takes anywhere from 2-6 weeks. At
temperatures below 70F, it takes even longer to cycle a tank. In
comparison to other types of bacteria, nitrifying bacteria grow
slowly. Under optimal conditions, it takes fully 15 hours for a
colony
to double in size!
It is sometimes possible to speed up the cycling time. Some common
procedures for this are detailed later in this section.
Warning: _AVOID THE TEMPTATION TO GET MORE FISH UNTIL AFTER YOUR
TANK
HAS FULLY CYCLED!_ More fish means more ammonia production,
increasing
the stress on all fish and the likelihood of fish deaths. Once
ammonia
levels reach highly stressful or toxic levels, your tank has
succumbed
to ``New Tank Syndrome''; the tank has not yet fully cycled, and
the
accumulating ammonia has concentrations lethal to your fish.
How Much Ammonia Is Too Much?
In an established tank, ammonia should be undetectable using
standard
test kits available at stores. The presence of detectable levels
indicates that your bio filter is not working adequately, either
because your tank has not yet cycled, or the filter is not
functioning
adequately (e.g., too small for fish load, clogged, etc.) It is
imperative that you address the problem (filter) in addition to the
symptoms (high ammonia levels).
The exact concentration at which ammonia becomes toxic to fish
varies
among species; some are more tolerant than others. In addition,
other
factors like water temperature and chemistry play a significant
role.
For example, ammonia (NH3) continually changes to ammonium (NH4+)
and
vice versa, with the relative concentrations of each depending on
the
water's temperature and pH. Ammonia is extremely toxic; ammonium is
relatively harmless. At higher temperatures and pH, more of the
nitrogen is in the toxic ammonia form than at lower pH.
Standard test kits measure total ammonia (ammonia plus ammonium)
without distinguishing between the two forms. The following chart
gives the maximum long-term level of ammonia-N in mg/L (ppm) that
can
be considered safe at a given temperature and pH. Again, note that
a
tank with an established biological filter will have no detectable
ammonia; this chart is provided only for emergency purposes. If
your
levels approach or exceed the levels shown, take emergency action
_IMMEDIATELY_.
Water Temperature
pH 20C (68F)
25C (77F)
_________________________________
6.5 15.4
11.1
7.0 5.0
3.6
7.5 1.6
1.2
8.0 0.5
0.4
8.5 0.2
0.1
Minimizing Fish Stress During Initial Cycling
Should ammonia levels become high during the cycling process,
corrective measures will need to be taken to prevent fish deaths.
Most
likely, you will simply perform a sequence of partial water
changes,
thereby diluting ammonia to safer concentrations.
As a final caution, several commercial products (e.g., ``Amquel''
or
``Ammo-Lock'') safely neutralize ammonia's toxicity. Amquel does
not
remove the ammonia, it simply neutralizes its toxicity. Biological
filtration is still needed to convert the (neutralized) ammonia to
nitrite and nitrate. Thus, adding Amquel causes the ammonia
produced
by the fish to be neutralized instantly, yet still allows the
nitrogen
cycle to proceed. Using Amquel during the cycling phase has one
significant drawback, however. Amquel (and similar products) may
cause
ammonia test kits to give false readings, making it difficult to
determine exactly when cycling has completed. See the TEST KIT
SECTION
for details.
It is also possible to cycle a tank without ever adding fish. The
role
fish provide in the cycling process is simply their steady
production
of ammonia; the same effect can be achieved by adding chemical
forms
of ammonia manually (e.g., ammonium chloride). However, it is a bit
more complicated than using fish because the water chemistry needs
to
be monitored more closely in order to add the proper amount of
ammonia
on a day-to-day basis.
Speeding Up Cycling Time
(For the Impatient)
The nitrogen cycle can be sped up or ``jump started'' in a number
of
ways. Unfortunately, they require access to an established tank,
which
a beginning aquarist may not have available. The basic idea is to
find
an established tank, take some of the bacteria out of it and place
them in the new tank.
Most filters have some sort of foam block or floss insert on which
nitrifying bacteria attach. Borrowing all or part of such an insert
and placing it in the new tank's filter gets things going more
quickly.
If the established tank uses an undergravel filter, nitrifying
bacteria will be attached to the gravel. Take some of the gravel (a
cup or more) and hang it in a mesh bag in your filter (if you can),
or
lay it over the top of the gravel in the new tank (if it has an UGF).
If you have a box, sponge or corner filter, simply connect it to an
established aquarium and let it run for a week or so. Bacteria in
the
water will establish a bed in the new filter. After a week, move
the
now ``seasoned'' filter to the new tank.
More recently, products containing colonies of nitrifying bacteria
have become available at pet shops (e.g., ``Fritz'', ``Bio-zyme'',
``Cycle''). In theory, adding the bacteria jump-starts the
colonization process as above. Net experience with such products
has
been mixed; some folks report success, while others report they
don't
work at all. In principle, such products should work well. However,
nitrifying bacteria cannot live indefinitely without oxygen and
food.
Thus, the effectiveness of a product depends on its freshness and
can
be adversely effected by poor handling (e.g., overheating).
Unfortunately, these products don't come with a freshness date, so
there is no way to know how old they are.
Some (not many) aquarium stores will provide aquarium buyers with a
cup of gravel from an established tank. A word of caution is
appropriate here. Due to the nature of the business, tanks in
stores
are very likely to contain unwanted pathogens (bacteria, parasites,
etc.); you don't want to add them to an established tank. For
someone
setting up their very first tank, however, all fish will probably
be
purchased from the same store, so the danger is relatively small,
as
the newly purchased fish will have been exposed to the same
pathogens.
If possible, seed a filter with bacteria from a non-store tank.
Of course, there are many variations on the above that work.
However,
it is a bit difficult to give an exact recipe that is guaranteed to
work. It is advisable to take a conservative approach and not add
fish
too quickly. In addition, testing the water to be sure nitrates are
being produced eliminates the guesswork of determining when your
tank
has cycled.
NEXT: Practical Water Chemistry
UP: Contents
BEGINNER FAQ: PRACTICAL WATER CHEMISTRY
What You Need to Know About Water Chemistry, and Why
Water in nature is rarely pure in the ``distilled water'' sense; it
contains dissolved salts, buffers, nutrients, etc., with exact
concentrations dependent on local conditions. Fish (and plants)
have
evolved over millions of years to the specific water conditions in
their native habitats and may be unable to survive in significantly
different environments.
Beginners (especially the lazy) should take the easy approach of
selecting fish whose needs match the qualities of their normal tap
water. Alternatively, an advanced (and energetic!) aquarist can
change
the water characteristics to match the fish's needs, though doing
so
is almost always more difficult than first appears. In either case,
you need to know enough about water chemistry to ensure that the
water
in your tank has the right properties for the fish you are keeping.
Water has four measurable properties that are commonly used to
characterize its chemistry. They are pH, buffering capacity,
general
hardness and salinity. In addition, there are several nutrients and
trace elements.
pH
pH refers to water being either an acid, base, or neither
(neutral). A
pH of 7 is said to be neutral, a pH below 7 is ``acidic'' and a pH
above 7 is ``basic'' or ``alkaline''. Like the Richter scale used
to
measure earthquakes, the pH scale is logarithmic. A pH of 5.5 is 10
times more acidic than water at a pH of 6.5. Thus, changing the pH
by
a small amount (suddenly) is more of a chemical change (and more
stressful to fish!) than might first appear.
To a fishkeeper, two aspects of pH are important. First, rapid
changes
in pH are stressful to fish and should be avoided. Changing the pH
by
more than .3 units per day is known to stress fish. Thus, you want
the
pH of your tank to remain constant and stable over the long haul.
Second, fish have adapted to thrive in a (sometimes narrow) pH
range.
You want to be sure that your tank's pH matches the specific
requirements of the fish you are keeping.
Most fish can adjust to a pH somewhat outside of their optimal
range.
If your water's pH is naturally within the range of 6.5 to 7.5, you
will be able to keep most species of fish without any problems. If
your pH lies within this range, there is probably no need to adjust
it
upward or downward.
Buffering Capacity (KH, Alkalinity)
Buffering capacity refers to water's _ability_ to keep the pH
stable
as acids or bases are added. pH and buffering capacity are
intertwined
with one another; although one might think that adding equal
volumes
of an acid and neutral water would result in a pH halfway in
between,
this rarely happens in practice. If the water has sufficient
buffering
capacity, the buffering capacity can absorb and neutralize the
added
acid without significantly changing the pH. Conceptually, a buffer
acts somewhat like a large sponge. As more acid is added, the
``sponge'' absorbs the acid without changing the pH much. The
``sponge's'' capacity is limited however; once the buffering
capacity
is used up, the pH changes more rapidly as acids are added.
Buffering has both positive and negative consequences. On the plus
side, the nitrogen cycle produces nitric acid (nitrate). Without
buffering, your tank's pH would drop over time (a bad thing). With
sufficient buffering, the pH stays stable (a good thing). On the
negative side, hard tap water often almost always has a large
buffering capacity. If the pH of the water is too high for your
fish,
the buffering capacity makes it difficult to lower the pH to a more
appropriate value. Naive attempts to change the pH of water usually
fail because buffering effects are ignored.
In freshwater aquariums, most of water's buffering capacity is due
to
carbonates and bicarbonates. Thus, the terms ``carbonate hardness''
(KH), ``alkalinity'' and ``buffering capacity'' are used
interchangeably. Although technically not the same things, they are
equivalent in practice in the context of fishkeeping. Note: the
term
``alkalinity'' should not be confused with the term ``alkaline''.
Alkalinity refers to buffering, while alkaline refers to a solution
that is a base (i.e., pH > 7).
How much buffering does your tank need? Most aquarium buffering
capacity test kits actually measure KH. The larger the KH, the more
resistant to pH changes your water will be. A tank's KH should be
high
enough to prevent large pH swings in your tank over time. If your
KH
is below roughly 4.5 dH, you should pay special attention to your
tank's pH (e.g, test weekly, until you get a feel for how stable
the
pH is). This is _ESPECIALLY_ important if you neglect to do
frequent
partial water changes. In particular, the nitrogen cycle creates a
tendency for an established tank's pH to decrease over time. The
exact
amount of pH change depends on the quantity and rate of nitrates
produced, as well as the KH. If your pH drops more than roughly two
tenths of a point over a month, you should consider increasing the
KH
or performing partial water changes more frequently. KH doesn't
affect
fish directly, so there is no need to match fish species to a
particular KH.
Note: it is not a good idea to use distilled water in your tank. By
definition, distilled water has essentially no KH. That means that
adding even a little bit of acid will change the pH significantly
(stressing fish). Because of its instability, distilled (or any
essentially pure water) is never used directly. Tap water or other
salts must first be added to it in order to increase its GH and KH.
General Hardness (GH)
General hardness (GH) refers to the dissolved concentration of
magnesium and calcium ions. When fish are said to prefer ``soft''
or
``hard'' water, it is GH (not KH) that is being referred to.
Note: GH, KH and pH form the Bermuda's Triangle of water chemistry.
Although the three properties are distinct, they all interact with
each other to varying degrees, making it difficult to adjust one
without impacting the other. That is one reason why beginning
aquarists are advised _NOT_ to tamper with these parameters unless
absolutely necessary. As an example, ``hard'' water frequently
often
comes from limestone aquifers. Limestone contains calcium
carbonate,
which when dissolved in water increases both the GH (from calcium)
and
KH (from carbonate) components. Increasing the KH component also
usually increases pH as well. Conceptually, the KH acts as a
``sponge'' absorbing the acid present in the water, raising the
water's pH.
Water hardness follows the following guidelines. The unit dH means
``degree hardness'', while ppm means ``parts per million'', which
is
roughly equivalent to mg/L in water. 1 unit dH equals 17.8 ppm
CaCO3.
Most test kits give the hardness in units of CaCO3; this means the
hardness is equivalent to that much CaCO3 in water but does not
mean
it actually came from CaCO3.
General Hardness
0 - 4 dH, 0 -
70 ppm : very soft
4 - 8 dH, 70 - 140 ppm :
soft
8 - 12 dH, 140 - 210 ppm : medium
hard
12 - 18 dH, 210 - 320 ppm : fairly hard
18 - 30 dH, 320 - 530 ppm : hard
higher : liquid rock (Lake Malawi and Los Angeles, CA)
Salinity
Salinity refers to the total amount of dissolved substances.
Salinity
measurements count both GH and KH components as well as such other
substances as sodium. Knowing water's salinity becomes important in
salt water aquariums. In freshwater tanks, knowing pH, GH and KH
suffices.
Salinity is usually expressed in terms of its specific gravity, the
ratio of a solution's weight to weight of an equal volume of
distilled
water. Because water expands when heated (changing its density), a
common reference temperature of 59F degrees is used. Salinity is
measured with a hydrometer, which is calibrated for use at a
specific
temperature (e.g., 75F degrees is common).
One component of salinity that neither GH or KH includes is sodium.
Some freshwater fish tolerate (or even prefer) a small amount of
salt
(it stimulates slime coat growth). Moreover, parasites (e.g., ick)
do
not tolerate salt at all. Thus, salt in concentrations of (up to) 1
tablespoon per 5 gallons can actually help prevent and cure ick and
other parasitic infections.
On the other hand, some species of fish do not tolerate _ANY_ salt
well. Scaleless fish (in general) and some Corydoras catfish are
far
more sensitive to salt than most freshwater fish. Add salt only if
you
are certain that all of your tank's inhabitants prefer it or can at
least tolerate it.
Nutrients and Trace Elements
In addition to GH, KH, pH and salinity, there are a few other
substances you may want to know about. Most tap water contains an
assortment of nutrients and trace elements in very low
concentrations.
The presence (or absence) of trace elements can be important in
some
situations, specifically:
* nitrates, which are discussed in great length in this
FAQ in
conjunction with the NITROGEN CYCLE;
* phosphates, the second most prominent nutrient.
Phosphates have
been linked to algae growth. If you have
persistent algae
problems, high phosphates may be a
contributing factor. In a plant
tank, ideal phosphate levels are .2 mg/L or
lower. To control
algae, frequent partial water changes are
often recommended to
reduce nutrient levels. If your tap water
contains excess
phosphate, water changes may be aggravating
the situation. Your
local water company can tell you what the
exact phosphate levels
are.
* iron, manganese and other trace elements. Plants need
iron in
trace quantities to grow. Tap water in many
areas contains no iron
at all. Consult the PLANT FAQ for more
details.
Altering Your Water's Chemistry
Hardening Your Water (Raising GH and/or KH)
The following measurements are approximate; use a test kit to
verify
you've achieved the intended results.
To raise both GH and KH simultaneously, add calcium carbonate
(CaCO3).
1/2 teaspoon per 50 liters of water will increase both the KH and
GH
by about 3-4 dH. Alternatively, add some sea shells, coral,
limestone,
marble chips, etc. to your filter.
To raise the KH without raising the GH, add sodium bicarbonate
(NaHCO3), commonly known as baking soda. One teaspoon per 50 Liters
raises the KH by about 4 dH. Sodium bicarbonate drives the pH
towards
an equilibrium value of 8.2.
Raising and Lowering pH
One can raise or lower pH by adding chemicals. Because of
buffering,
however, the process is difficult to get right. Increasing or
decreasing the pH (in a stable way) actually involves changing the
KH.
The most common approach is to add a buffer whose equilibrium holds
the pH at the desired value.
Muriatic (hydrochloric) acid can be used to reduce pH. Note that
the
exact quantity needed depends on the water's buffering capacity. In
effect, you add enough acid to use up all the buffering capacity.
Once
this has been done, decreasing the pH is easy. However, it should
be
noted that the resultant lower-pH water has much less KH buffering
than it did before, making it more susceptible to pH swings when
(for
instance) nitrate levels rise. Warning: It goes without saying that
acids are _VERY_ dangerous! Do not use this approach unless you
know
what you are doing, and you should treat the water _BEFORE_ adding
it
to the aquarium.
Products such as ``pH-Down'' are based on a phosphoric acid buffer.
Phosphoric acid tends to keep the pH at roughly 6.5, depending on
how
much you use. Unfortunately, use of phosphoric acid has the _BIG_
side
effect of raising the phosphate level in your tank, stimulating
algae
growth. It is difficult to control algae growth in a tank with
elevated phosphate levels. The only advantage over hydrochloric
acid
is that pH will be somewhat better buffered at its lower value.
One safe way to lower pH _WITHOUT_ adjusting KH is to bubble CO2
(carbon dioxide) through the tank. The CO2 dissolves in water, and
some of it forms carbonic acid. The formation of acid lowers the
pH.
Of course, in order for this approach to be practical, a steady
source
of CO2 bubbles (e.g. a CO2 tank) is needed to hold the pH in place.
As
soon as the CO2 is gone, the pH bounces back to its previous value.
The high cost of a CO2 injection system precludes its use as a pH
lowering technique in most aquariums (though see the PLANT FAQ for
inexpensive do-it-yourself alternatives). CO2 injection systems are
highly popular in heavily-planted tanks, because the additional CO2
stimulates plant growth.
Softening Your Water (i.e., lowering GH)
Some fish (e.g., discus, cardinal tetras, etc.) prefer soft water.
Although they can survive in harder water, they are unlikely to
breed
in it. Thus, you may feel compelled to soften your water despite
the
hassle involved in doing so.
Typical home water softeners soften water using a technique known
as
``ion exchange''. That is, they remove calcium and magnesium ions
by
replacing them with sodium ions. Although this does technically
make
water softer, most fish won't notice the difference. That is, fish
that prefer soft water don't like sodium either, and for them such
water softeners don't help at all. Thus, home water softeners are
not
an appropriate way to soften water for aquarium use.
Fish stores also market ``water softening pillows''. They use the
same
ion-exchange principle. One ``recharges'' the pillow by soaking it
in
a salt water solution, then places it in the tank where the sodium
ions are released into the water and replaced by calcium and
magnesium
ions. After a few hours or days, the pillow (along with the calcium
and magnesium) are removed, and the pillow recharged. The pillows
sold
in stores are too small to work well in practice, and shouldn't be
used for the same reason cited above.
Peat moss softens water and reduces its hardness (GH). The most
effective way to soften water via peat is to aerate water for 1-2
weeks in a bucket containing peat moss. For example, get a
(plastic)
bucket of the appropriate size. Then, get a large quantity of peat
(a
gallon or more), boil it (so that it sinks), stuff it in a pillow
case, and place it in the water bucket. Use an air pump to aerate
it.
In 1-2 weeks, the water will be softer and more acidic. Use this
aged
water when making partial water changes on your tank.
Peat can be bought at pet shops, but it is expensive. It is much
more
cost-effective to buy it in bulk at a local gardening shop. Read
labels carefully! You don't want to use peat containing fertilizers
or
other additives.
Although some folks place peat in the filters of their tanks, the
technique has a number of drawbacks. First, peat clogs easily, so
adding peat isn't always effective. Second, peat can be messy and
may
cloud the water in your tank. Third, the exact quantity of peat
needed
to effectively soften your water is difficult to estimate. Using
the
wrong amount results in the wrong water chemistry. Finally, when
doing
water changes, your tank's chemistry changes when new water is
added
(it has the wrong properties). Over the next few days, the
chemistry
changes as the peat takes effect. Using aged water helps ensure
that
the chemistry of your tank doesn't fluctuate while doing water
changes.
Hard water can also be softened by diluting it with distilled water
or
R/O water. R/O (reverse-osmosis) water is purified water made by a
R/O
unit. Unfortunately, R/O units are too expensive ($100-$500) for
most
hobbyists. R/O water can also be purchased at some fish stores, but
for most folks the expense and hassle are not worth it. The same
applies to distilled water purchased at grocery stores.
NEXT: Test Kits
UP: Contents
BEGINNER FAQ: TEST KITS
WHICH ARE USEFUL?
There is a seemingly endless array of test kits for testing
everything
from ammonia levels to phosphate levels. Does one really need to
buy
them? The quick answer is no. It is quite possible to have a
healthy
tank without ever buying a single test kit. However, test kits are
extremely useful at eliminating guesswork when something goes wrong
(e.g., fish appear stressed or die). In the following, we describe
the
test kits that are most useful and the conditions under which they
are
useful.
Ammonia Test Kit
Get one. Ammonia test kits are cheap ($5-10) and will tell you
whether
your tank has elevated ammonia levels. This is useful in two
circumstances. First, during the tank-cycling phase, regular
testing
for ammonia will tell you when the first phase of the nitrogen
cycle
has completed. Second, should you have unexplained fish deaths,
testing for ammonia verifies that your biological filter is (or is
not) working correctly. Note that even in an established tank, the
biological filter can sometimes weaken or fail outright. Common
causes
include
* not cleaning the filter regularly (water can't flow
through a
clogged filter, where the nitrifying
bacteria reside),
* naively adding fish medicines (antibiotics kill
nitrifying
bacteria (oops) as well as disease carrying
ones),
* having too small a filter for the fish load, etc.
Be warned: if you have fish deaths and subsequently ask the net (or
a
fish store) for advice, the first question asked will be ``What are
your ammonia (and nitrite) levels?''.
Ammonia levels are measured in ppm. At concentrations as low as
.2-.5
ppm (for some fish), ammonia causes rapid death (consult the
CYCLING
SECTION for further details). Even at levels above 0.01-0.02 ppm,
fish
will be stressed. Common test kits don't register such low
concentrations. Thus, test kits should _NEVER_ detect ammonia in an
established tank. If your test kit detects _ANY_ ammonia, levels
are
too high and are stressing fish. Take corrective action immediately
by
changing water and identifying the source of the problem.
Warning: Amquel and other similar ``ammonia-neutralizing'' water
additives are incompatible with most ammonia test kits. Water
treated
with Amquel will falsely test positive for ammonia, even when
ammonia
is not present. Test kits using the ``Nessler'' method are known to
give false readings under such conditions.
Nitrite Test Kit
You might want to get one of these; nitrite kits are cheap ($5-10)
and
are useful in the same circumstances where an ammonia test is
useful.
The only time a nitrite kit provides information that an ammonia
kit
can't is while testing for completion of the second phase of the
nitrogen cycle (see the CYCLING SECTION). As in the case for
ammonia,
if your test kits detects nitrite, your biological filter is not
working adequately. Once a tank has cycled, nitrite kits are pretty
much useless. (If the bio filter in an established tank isn't
working,
both ammonia and nitrite levels will be elevated.)
Nitrite is an order of magnitude less toxic than ammonia. Thus, one
common saying about tank cycling is: ``if your fish survive the
ammonia spike, they'll probably survive the nitrite spike and the
rest
of the cycling process.'' However, even at levels above .5 ppm,
fish
become stressed. At 10-20 ppm, concentrations become lethal.
Nitrate Test Kit
Get this kit! Nitrate levels increase over time in established
tanks
as the end result of the nitrogen cycle. (The only exception to
this
rule is _heavily_-planted tanks and some reef tanks, which _MAY_ be
able to consume nitrogen faster than it is produced.) Because
nitrates
become toxic at high concentrations, they must be removed
periodically
(e.g., through regular water changes). Having a nitrate test kit
helps
you determine whether or not your water changes are removing
nitrates
quickly enough.
Nitrates become toxic to fish (and plants) at levels of 50-300 ppm,
depending on the fish species. For fry, however, much lower
concentrations become toxic.
Note: A nitrate test kit is only of limited value in determining
whether the nitrogen cycle has completed. Most nitrate test kits
actually convert nitrate to nitrite first, then test for the
concentration of nitrite. That is, they actually measure the
combined
concentration of nitrite and nitrate. In an established tank,
nitrite
levels are essentially zero, and the kits do properly measure
nitrate
levels. While a tank is cycling, however, a nitrate kit can't tell
you
how much of the reading (if any) comes from nitrate rather than
nitrite.
pH Test Kit
Get one; these kits are extremely cheap, so there is no excuse for
not
owning one. You will want to know the pH of your tap water so that
you
can select fish whose requirements meet your water conditions. In
addition, you will periodically want to check your tank's pH so
that
you can be sure it stays stable and doesn't increase or decrease
significantly over time.
In some cases, tank decorations (e.g., driftwood) or gravel (e.g.,
made of coral, shells or limestone) change the pH of your water.
For
example, tank items may slowly leach ions into your tank's water,
raising the GH and KH (and pH). With driftwood, it is not uncommon
to
have the wood slowly leach tannins that lower the pH.
General Hardness (GH) Kit
You may want to get one of these, but having one is not critical.
You
don't need to know the exact hardness level. Knowing whether your
water is ``soft'', ``very soft'', etc. is good enough. Your local
fish
store may be able to give you sufficient information.
Alternatively,
call your water utility (see the TAPWATER SECTION of this FAQ).
Carbonate Hardness (KH) Kit
This kit is not critical to have. By regularly monitoring the pH,
you
can figure out whether your KH is ``high enough''. That is, the KH
should be high enough that your pH stays stable over time. If you
have
trouble keeping the pH stable, you may want to increase your tank's
buffering capacity. Your local fish store may be able to give you
sufficient information as to your KH value. Alternatively, call
your
water utility.
A KH kit is, however, indispensable to plant enthusiasts who use
CO2
injection. It is also strongly recommended that you get one if you
want to change the pH of your water, and it is a very useful
diagnostic tool if you are experiencing pH stability problems.
NEXT: Fish Stress
UP: Contents
BEGINNER FAQ:
FISH STRESS AND HEALTHY FISHKEEPING
What Stress Means, and Why it is Bad for Your Fish.
Most fish can tolerate environmental conditions that differ
somewhat
from the natural conditions in which they evolved. This does not
mean,
however, that they will be as healthy or live their full normal
life
span. For example, keeping a fish in water that is cooler (or
warmer)
than its preferred condition forces its body organs to work harder
to
keep it alive. That is, such conditions place the fish under
increased
_stress_.
Increased stress reduces a fish's ability to ward off diseases and
heal itself (e.g., if its fins get nicked, or parasites get
introduced
into the tank with newly purchased fish). In addition, stress
reduces
a fish's ability to breed successfully and shortens its natural
life
span. A small amount of stress by itself is not usually fatal, but
as
stress levels increase, a fish's ability to cope with it decreases.
Thus, one of the most important goals of a fishkeeper is to remove
sources of stress wherever possible.
It should be noted that eliminating stress does not guarantee that
your tank will be healthy. But it significantly increases the odds.
Many netters boast regularly about how they've kept fish
(apparently)
``healthy and happy'' for long periods of time under (apparently)
highly stressful conditions. Such aquarists are sitting on a
time-bomb; the not uncommon followup story will refer to one fish
getting sick, then another, with an end result of multiple fish
deaths. Reducing stress simply increases the likelihood that a tank
will stay healthy (much the same way as eating right, exercising
and
getting the proper amount sleep is generally associated with a long
healthy life for humans).
Common Causes of Stress in the Aquarium
In this section, we list some of the more common stress-inducing
conditions. In all cases, the level of stress induced by a specific
factor is highly species-dependent. You should be aware of the type
of
stress that will be present in your tanks and select fish known to
tolerate such conditions well. For example, if your water is hard
and
alkaline, you're best off selecting fish that thrive under such
conditions.
Nitrogen compounds (ammonia, nitrite and nitrate) have varying
degrees
of toxicity and are stressful at all levels. Ammonia is toxic in
low
concentrations and severely stresses fish under _ANY_
concentration.
Consequently, a healthy aquarium must have an adequate biological
filter that quickly converts ammonia to nitrite (and nitrate).
Although significantly less toxic than ammonia or nitrite, nitrate
also stresses fish. Thus, a means of removing excess nitrate (e.g.,
through regular water changes) helps keep an aquarium healthy.
The water temperature of your tank should match the needs of its
inhabitants. Keeping water temperature too cold or too warm for a
particular species will stress those fish. For example, goldfish
prefer cooler temperatures (under 70F) than most tropical fish
(goldfish survive winters in ponds where temperatures approach
freezing), guaranteeing that a tank containing both goldfish and
tropicals will either be too cold or too warm for some of the
inhabitants.
Some fish prefer soft water, others prefer hard water. Keeping a
soft-water preferring fish in harder water (and vice versa) is
stressful.
Some fish prefer acidic water, some prefer alkaline water, others
prefer water with a neutral pH. (Some fish don't care too much.)
Some fish live in brackish water conditions; they will do better in
water with a small amount of added salt. Other species are
extremely
intolerant of salt. Add salt only if all of a tank's inhabitants
can
tolerate salinity. Mollies, for example are known to like salt,
whereas many species of catfish tolerate no salt at all. In
general,
fish lacking scales (or having small scales) don't tolerate salt
well.
The amount of physical space required for a particular fish depends
on
its species. Some fish do just fine in a 10g tank, others need 100g
or
more. Keeping a fish in a tank that is too small for it increases
the
level of stress (on everyone), frequently leading to increased
aggression among tank inhabitants. Note also that the amount of
space
required may change should fish pair off to breed. Cichlids, for
example, claim a portion of the tank for themselves when in
breeding
form, chasing away any fish that encroach on their territory. Thus,
the onset of breeding behaviors frequently increases stress levels.
Not all species of fish mix well with others. As an obvious
example,
most cichlids will eat smaller tank inhabitants (e.g., anything
they
can fit in their mouths). Even if too big to be eaten, however,
peaceful fish will be stressed if kept with aggressive fish that
chase
them around all day. Moreover, many fish communicate through
behav |