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Aquarium Setup

Aquarium Setup - Fish Tanks

55 Gallon Aquarium Setup
55 Gallon Aquarium Setup

Fish tanks are mainly made of glass, but acrylic is sometimes used as well. The size of the tank you will need for your aquarium setup depends on the type and number of fish that you plan to have. A general rule is to allow one gallon of water for each one inch of fish. This equates to about one centimetre for each litre of water. For example 20 neons would be manageable in a 20 gallon tank.

If the fish tank is just being established be sure to read our section on Cycling a New Tank & Water Quality. With a well balanced aquarium and a proper filter, you will be able to exceed these limits. One of the main factors in supporting fish is the surface area of the water.

Glass bowls are only suitable for Bettas. Goldfish shouldn't be placed in small glass bowls, because they need more oxygen and are messier than most fish. A glass bowl is usually smaller at the top and reduces the exposure to oxygen. Since bettas can breathe air directly, this isn't an issue for them.

For value in aquariums, it's hard to beat department stores. They provide excellent aquariums, complete with heater, filter, canopy and fluorescent lighting. Fluorescent lighting will produce much better lighting for viewing your fish than incandescent light bulbs will. Many department store aquarium products are actually rebranding of Marineland inventories.

Place the tank in an area which gets as little direct light as possible. This will help reduce the build up of algae, reduce temperature build up from the sun and provide better viewing. You will notice that most retailers don't have windows near their fish displays.

Also, check out Bernie's Aquarium Decor Tips.

Aquarium Setup - Tank Volume Calculator

It's important to have the right tank size before you begin your aquarium setup. When you buy a new tank, they tell you the volume. What about when you buy a used tank? Ever wonder how many gallons the tank is? All you need is a tape measure and the tank volume calculator below. The tank volume calculator will tell you how many gallons or liters there are in your tank.

Tank Volume Calculator - Inches

Length inches
Width   inches
Height  inches

The tank volume for in. by in. by in. is:

0.00 US gallons or 0.00 UK gallons or 0.00 liters

Tank Volume Calculator - Cm

Length cm
Width   cm
Height  cm

The tank volume for cm by cm by cm is:

0.00 liters or 0.00 US gallons or 0.00 UK gallons

Aquarium Setup - Filters

A filter is essential for maintaining clear water in an aquarium. For fish that require extremely clear water, such as cichlids, more than one type of filter should be considered. This also provides a form of insurance in case one of the filters stops working. There are three types of filtration:

  • Mechanical - removes particles from the water
  • Biological - provides areas for helpful micro-organisms to live
  • Chemical - changes water quality by adding oxygen or removing ammonia

Aquarium Setup - External Power Filter

Liberty External Power Filter

The External Power Filter is very common and inexpensive. It draws water from the tank and passes it through filter material such as sponges, carbon and zeolite. The sponge can provide mechanical filtration by removing particles. It can also provide biological filtration by providing a perfect surface for micro-organisms to grow on. Rinse the sponge instead of throwing it away - it is housing valuable life forms that can't be seen. External Power filters often contain zeolite to remove ammonia and carbon to increase oxygen content. This is referred to as chemical filtration. The carbon and zeolite should be removed when using medications, to prevent the medication from being quickly removed from the water. Evaporation is significant with External Power Filters, but less than if a Bio Wheel is installed.. External Power Filters are sold with aquariums from Walmart. Brand names include AquaClear from Hagen, the Regent, which is produced by Marineland and the Liberty, which is produced by Eheim.

Comments by LittleHippyGirl: Aquaclear filters are great because...
-They're Powerful
-They're Silent
-Have lots of space for beneficial bacteria
-You can easily customize the filter (ex: more bio-max, 2 sponges, add chemical pouches...)
-You can easily add or remove a pouch of carbon
-You can adjust the flow rate
Can you tell these are my favorite HOB (Hang on Back) filters? If you have a 30 gallon tank, an Aquaclear 300 should be all the filtration you need, and depending on the size and strength of your fish, you probably want to run it on a lower setting. Remember to never ever clean the bio-max, only the sponges when they clog. If you do, you could upset your nitrogen cycle. Also, added filtration doesn't really get rid of waste, it just moves it. Regular water changes and siphoning is the best answer

Comment by Tim: Aquaclear filters do tend to stick after they've been turned off. I use a pencil to reach down and give it a spin while the power is on to get them going again.

Aquarium Setup - Bio Wheel External Power Filter

Bio Wheel External Power Filter

The Bio Wheel External Power Filter is more difficult to obtain, but is highly recommended for its biological filtration. Micro-organisms develop in the wheel and the constant aeration from the turning wheel increases the capability of these life forms to convert harmful ammonia, as well as supplying oxygen to the water. The filter is replaced, but the bio-wheel is retained.

With a Bio Wheel External Power Filter, gravel isn't really even necessary, because the wheel provides the biological filtration. Bio Wheels have a downside, in that they will put fish at risk if the wheel stops moving, as half the helpful micro-organisms will no longer be available. A Bio Wheel also increases evaporation even more than a simple External Power Filter. Make sure you remove water instead of just topping up for evaporation, to prevent minerals from building up in the aquarium. Bio Wheels like the Penguin and the Emperor are sold by Marineland. The Eclipse Bio Wheel by Marineland places the filter in the canopy, so the aquarium will fit flush against a wall on an aquarium stand. The Eclipse places the lighting at the front of the tank, so your fish are better lit for viewing.

Aquarium Setup - External Canister Filter

Fluval External tropical fish aquarium Filter

The External Canister Filter allows the filter to be placed competely out of sight. The most commonly available external canister is the Fluval Canister Filter made by Hagen. These come with tubing to position the canister out of sight. They also allow a number of media to be added to the canister, such as zeolite, carbon and peat. They are mainly useful for chemical and mechanical filtering.

Aquarium Setup - Wet / Dry External Canister

Wet/dry Eheim Canister tropical fish aquarium

The Wet/dry External Canister Filter is also known as a trickle filter. It uses a pump to remove water from the tank and then pass it down a tower. The tower is filled with material such as bioballs for biological filtration. The filter material is continuously exposed to water and air, thus increasing the capacity for helpful bacteria to form in well oxygenated water. This explains the term wet/dry.

The wet/dry external canister filter is similar to a power filter but allows the water to flow completely down past the filter while still exposing the filter element to air. It is also larger and more powerful than an power filter. Wet/dry filters can also have chemical and mechanical filtration devices attached to them. Wet/dry filters require very little maintenance, but, as with the power filter, evaporation is a problem. There are numerous varieties of wet/dry filters and it is common for aquarists to build their own version.

Aquarium Setup - Under Gravel Filter

Tropical fish aquarium Under gravel filter Rena aquarium air pump

Under Gravel Filter has declined in popularity, because of some of the risks in using one. The Under Gravel Filter provides one of the best methods of biological filtration. A small external air pump provides circulation. The air pump draws water through the gravel. This promotes excellent micro-organism growth to convert harmful ammonia in the tank. One reason the Under Gravel Filter isn't as popular as other filters is because areas of gravel not covered by the filter can become toxic. If your Under Gravel Filter doesn't cover nearly all of the bottom surface, it shouldn't be used. Be careful about turning off the air pump too, since this will kill micro-organisms and cause an ammonia spike. Despite these downsides, an Under Gravel Filter can outperform an External Power Filter with a Bio Wheel. The underground filter will also need an air pump to power it. Rena makes an air pump which is highly rated.

Aquarium Setup - Internal Canister Filter

Lustar Hydro-Sponge tropical fish aquarium filter Rena tropical fish aquaruim canister aquarium filter

The Internal Canister Filter uses air to force water through a filter material in the tank, such as a sponge or in days gone by - fiber glass. Internal canister filters are not frequently used in home aquariums as they take up valuable tank space and they are unsightly. They are more often used in retail stores and wholesale operations. The Lustar Hydro-Sponge is an inexpensive example which actually omits the canister. The sponge provides both mechanical and biological filtration. More expensive models include the Rena Internal Canister Filter by Aquarium Pharmaceuticals, the Professional II by Eheim and the Magnum canister filter by Marineland.

Many retail stores use more complicated systems which remove the water from the tank, filter it and return it. These systems can include pumps that change the water at the same time.

Aquarium Setup - Heaters

Tropical fish usually need a temperature near 75 F (24 C). Refer to the Fish Facts page for details on the temperature range for specific tropical fish species. Since a normal room temperature is slightly less than this, an aquarium heater is usually necessary, especially when winter starts influencing the inside temperature. Manufacturers suggest 3 - 5 watts per gallon.  Here's a rough guideline, but remember this is highly influenced by your room temperature:



50 10
100 20
150 30
2 - 100 50
2 - 125 80
2 - 150 100

For larger tanks, two heaters are preferable as this dissipates heat more evenly and also helps provide insurance in case one heater fails. The price does not increase substantially on larger wattage heaters. For example, it may only a few dollars more to get a 250 watt heater instead of a 150 watt from the same manufacturer. So, don't skimp on the wattage.

Aquarium heaters provide a heating element inside a glass casing. This insulates the electric operation from the water. Less expensive units cannot be fully submerged and must remain upright. If the heating coils aren't fully submersed, the unit will overheat and crack. Never operate an aquarium heater when it isn't in the water. If fully submersed these heaters will leak and short circuit. An example of these heaters is the Radiant by Hagen. This heater can be frustrating as the dial can easily be bumped, which causes wide swings in the aquarium temperature.

Aquarium heater

Submersible heaters are useful in breeding tanks where the water level has been lowered and an upright heater cannot operate. The Visi-Therm Deluxe by Marineland, with its easy to read temperature dial, is a favorite. Hagen makes a fully submersible heater. Ebo Jager has a good reputation for aquarium heaters. They use thicker glass, which reduces breakage. Their heaters have a precision of half a degree Fahrenheit and are adjustable from 64 - 94 degrees. Ebo Jager heaters are durable, accurate and inexpensive. Ebo Jager recently changed to the name Jager and Eheim has taken over responsibility for this product. Ebo Jagers are fully submersible, however some manufacture locations may not have approval for this to be disclosed on the product.

Don't forget to have a thermometer and check it occasionally too.

Aquarium Setup - Aquarium Plants

Amazon Sword Aquarium Plant

You are usually just about done your aquarium setup before you start shopping for aquarium plants. Aquarium plants make your aquarium tank look great. They also help your fish. Young tropical fish fry need places to hide. Cabomba aquarium plants and java moss are great hideouts. Even larger fish enjoy plants as a place to escape from other fish and from people staring into the tank.

You can plant cabomba into aquarium sand even though it doesn't have roots. You can build large forests of cabomba that way. Larger fish will uproot it quickly though. Cabomba also floats on the surface, which is a great way to protect young fry. Amazon sword aquarium plants are popular because they make an aquarium look exotic. Rotala Indica and Scarlet Hygrophila can be amazingly beautiful. Just make sure you choose the right fish for your plants. Cichlids love to uproot plants to pass the time of day. Follow the link for further information on specific aquarium plants.

Comments by LittleHippyGirl Low light and low mainenance plants include: Java Fern, anubias, java moss, anacharis, and crypts. If you have at least 3 watts per gallon, you may be able to keeps some aponogetons and vallisnaria. The first three plants should not be planted in gravel- they should be floated or tied to an ornament. Before you buy plants, be able to recognize those I mentioned.

Sand Instead of Gravel? Not a Great Idea

Using sand instead of gravel is not a great idea. It's a lot riskier to use sand in an aquarium. Some fish, like cichlids will dig through sand, which clouds up the tank. Another problem with sand is that it can build up toxic air pockets. To prevent toxic air pockets, you can add some Malaysian trapdoor snails. The snails will continuously dig through the sand to prevent build up. Unfortunately, snails breed quickly and can easily take over your entire aquarium. If you have too many snails, add a couple loaches because they will eat the snails. Filters can be a problem too. You cannot use under gravel filters with sand. Other filters can get clogged with sand. With all these problems it's easy to understand why it's much better to stick with gravel instead of sand?

Aquarium Setup - Removing Mineral Build Up

Question - I always get this white mineral stuff that build up on the the outside of the tank, like on the filter and the lid. What is the cause of this? Is there a way to avoid it or an easy way to clean it?

Comment by Dano - It is the salt, calicum, and other minerals that are left behind when the water evaporates....It is common to nearly all fish tanks..........Just wipe it off with Windex, venegar, or plain water....Don't get any of the cleaning agents in the tank water.............

Comment by Dave Gray - To add to what Dano has recommended I sometimes will use a green scotch brite pad that is wet with either tank or tap water and scrub tough spots and then dry with a T-shirt as I have found the T-shirt to be very absorbant. If what Dano has recommended and the scotch brite don't work then I move on to either Lime Away or CLR (Calcium, Lime, Rust). To use either of these products I apply the cleaner to a rag and then scrub the hard water spots off of the exterior of the tank and when I can't see the hard water spots I take a clean damp rag and rinse the cleaner off, and then do a final dry with a T-shirt (preferably one from the dirty clothes so you aren't dirtying up a clean T-shirt).

The One Inch per Gallon Rule by Bernie

No one really knows how or where the One Inch per Gallon Rule originated, but it is thought that it started in the 1960's. During that time, there was not the immense variety of fish on sale like the ones available to us today due to various reasons / regulations. One theory is that the size of fish available then was of the type that remained small, which made the One Inch per Gallon Rule quite appropriate & it has remained. Whether it is a myth, is still being debated to this day.

The One Inch per Gallon Rule is only a generalised rule that isn't set in stone. Rules can change with the times & this one may not apply as much as it once did. This One Inch per Gallon Rule really only applies to slim bodied, small fish that only grow to 2 or 3 inches. Many aquarists do not use this rule at all, but I do believe it is still a handy, useful guide for beginners or those keeping small fish like the aforementioned. Common sense has to come into play & the One Inch per Gallon Rule should not be taken literally & applied to all fish - you would not keep one 10 inch goldfish or an Oscar in a 10 gallon tank or ten 1 inch goldfish/Oscars in that tank.

The variables that need consideration when stocking are many:

Fish Size:

The Length of a fish is not the only thing to be calculated, its height/width need to be considered as well. If using the rule you must always use the size a fish will become when an adult, not the size it is when bought, so researching the fish first is necessary.


You need to know the swimming style of the fish - are they active swimmers that may need extra space. Feeding behavior - are they shy or slow eaters, do they prefer to eat from the top or bottom of a tank! Breeding behaviour - are they territorial etc. Compatibility - will it get along with the other fish, will it nip at other fish. Is it aggressive? many aquarium inhabitants may not be able to live together properly to the end of their natural life spans.


Fish may have different nutritional needs - some fish need more protein than others do. Are the fish herbivores, carnivores or omnivores? You need to know if you can meet each species requirements or is the diet of all the fish similar.


Some fish may need a planted tank, others non-planted. Lighting - some fish require very subdued lighting. Gravel or Sand -- some fish prefer sand, some require very smooth gravel. Rocks/caves - some fish need rocks, caves to hide in or for breeding. Temperature - Does it like cooler/warmer temperatures? High/low PH.

Surface Area of the Tank

It is normally better to have a wider, longer tank because it provides more surface space, which in turn provides more oxygen. Some fish e.g. Angelfish require a tall tank as well because of the height their fins grow to. Aquariums now come in a wide range of different shapes and sizes to meet the different swimming needs of fish. For example, 20 gallon tanks often come in high (24" long x 12" wide x 16" tall) or long (30" long x 12" wide x 12" tall) configurations.


A good filtration system can have a bearing on how many fish can be kept in a tank, although I do not go along with overstocking a tank. Are the fish messy eaters or big waste producers? Do they require more oxygen than others do? Do the fish require a slow or fast water current?

One Inch per Gallon - Conclusion

In conclusion, it is possible I have left something out but I think you get the idea, it is not only one but many factors that need to be considered & doing research into the fish you want to keep is vital before buying them.

It is my belief that any animal whose destination is to be kept in captivity as a pet has the right to live in an environment as close to their natural habitat as possible and one that will not severely stunt its growth or shorten its natural lifespan.