A healthy fish tank.

Keeping Your Fish Tank Healthy

Aquariums are fun and exciting, but they take some work. Here’s what you need to know when setting one up.

Your Brand New Fish Tank

Freshwater aquariums are by far the most popular way to keep ornamental fish other than goldfish, Japanese fighting fish, sunnies, or big mouth bass. A medium-sized aquarium is 10 to 30 gallons in volume and is recommended as a good starting point for new hobbyists.

Along with the supporting gear, these tanks are cheap and easy to handle. A brand-new 20-gallon complete setup will usually run you between $100 and $150. Avoid bargain special 10-gallon aquarium packages, since the components are usually not good quality.

Once you buy the tank, you need to decide where to put it. Keep in mind that a gallon of water weighs about eight pounds, so a 20-gallon aquarium with the filter, hood, rocks, gravel, plants, and fish can weigh close to a back-breaking 200 pounds.

Pet stores carry all kinds of sturdy, yet attractive, aquarium stands for holding your fish fantasy-land.

The Power Filter

Selecting a filter is serious business. In most cases, an undergravel biological filter or an out-of-tank power filter is adequate. Since you can never have too much filtration, you might want to combine an undergravel filter with an outside power filter. There are tons of good brands of filters on the market designed for all kinds of aquarium sizes.

If you have an undergravel filter, you will either need an air pump or something called a power head in order to pull water through the filter. This allows the filter to get the job done properly.


Lighting is super-important for a healthy aquariums, but it’s often neglected. Having the right light simulates natural daylight, as well as works to pretty up your tank. Fluorescent lamps, built into the tank hood, are usually best. Hoods are easy to install and keep fish from going AWOL. They also make it easy for you to get in and out of the tank for maintenance and feeding.

Avoid incandescent lights because they give off heat, which could stress out your fish as well as burn out faster than a fluorescent bulb.

Providing Heat

An essential part of a good tropical or subtropical aquarium is a heater. Most come with a built-in thermostat to take the guess work out of it. Freshwater tropical fish like water temperatures between 75 and 78 degrees Fahrenheit. On the other hand, saltwater tropical species prefer the water a little bit warmer, usually 78 to 82 degrees.

Goldfish and koi don’t need heaters and actually thrive at temperatures around 60 degrees. However, they can deal with a range of temperatures and, therefore, can be kept outdoors year-round in temperate climates.

Investing in a high-quality heater is a good way to protect your fish. Remember that aquarium heaters vary widely in terms of power, so make sure you speak to a pet store clerk about which one is best for you. You want to keep your fish warm, not broil them. A good rule of thumb is four watts of heater per gallon of water.

Clean Water

You don’t need a degree in chemistry to understand how to keep your water clean, but there are things you need to think about. These include ammonia, hardness, nitrate, oxygen, pH, salinity, and temperature. Use a good filter and don’t overload your aquarium with stuff like too many fish, snails, and food, and you’ve gone through half the battle.

Since poor tank water is the major cause of aquarium problems, changing the tank water monthly can keep your fish from getting sick or worse. Use a water quality test kit and change the equivalent of one percent of the aquarium’s water per day (or approximately 30 percent per month). Your pet store clerk or fish vet should be able to show you how to maintain the water for your fish.

Your vet is well trained in the area of medicine and diagnostics. They can give you helpful advice on disease prevention and control with regards to your pet fish. Not all veterinarians will treat pet fish or are knowledgeable about aquariums, but the number of fish vets is growing at a rapid pace.

Everything You’ll Need for a Perfect Fish Tank

Extras for a Happy Tank