I'm thinking about getting an aquarium. What equipment should I consider getting?

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.

All About 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 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 may require one more bucket of water be replaced in a larger 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. The number of fish 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.
  3. 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.
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!


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 become 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 disasterous.


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. Temperature-sensitive chemicals 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.


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., 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 as activated carbon.

One point about filtration cannot me made enough. ALL FISH TANKS MUST HAVE BIOLOGICAL FILTRATION. Although chemical filtration can remove ammonia under limited circumstances, they are NOT a general solution.

Typical filters perform some or all of the three filtration types by placing the 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 maintainance-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). Cannister 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 XXX.


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 section 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 in 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 light (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 leach carbonates into the tank raising its pH buffering capacity (see the chemistry section for details). When keeping African cichlids, this is usually 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.

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 (e.g., 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) flourescent 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 one can usually place more light bulbs (e.g., wattage) 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 flourescent 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 (e.g., special plant bulbs are useful). If you are interested in growing plants, be sure to consult section plant and lighting sections before purchasing your light and hood setup.

Whether or not you will be growing plants, flourescent lights are the way to go. Incandescent bulbs give off too much heat, causing your tank to overhead in the summer. Flourescent bulbs run cooler and use less electricity for the same amount of light. Note that in the summer time, even flourescent lighting can produce enough heat to lead to tank overheating problems, if your house gets warm (e.g, you live in the south 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 (e.g., 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 for both 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 particulary 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.

Consult the lighting section of the FAQ for more details if you are interested in growing plants.


A power head 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.


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 XXX 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.


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 section before purchasing your tank and hood.

Miscellaneous Cleaing 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 or "vacuum" your gravel. Many "water changing" hoses are available at local fish stores include a gravel cleaning attachment. The basic idea behind them is to connect a wide-mouthed tube to the end of the siphon hose that you use to stir up the gravel with. The gravel is too heavy to get sucked into the hose, but churning up the gravel frees up detritus, which 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 for the side 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 your entire arm in the tank. The best magnet cleaners are those that 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.


You will need at least one fish net, and having two is better; catching fish is easier if 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. Recommendations as to which tests to get are given in the Chemistry section XXX.

Where To Get Tank Hardwhere

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.

Next Section: Beginner: Identifying Good Stores