Your First Fish Tank

Keep your liquid oasis from turning mucky by following a few key tips. (Rebecca D'angelo For The Washington Post)

My first pet, a wide-eyed goldfish named Maureen that I got when I was 10 years old, lived a short but filthy life. As I carried her to the toilet two weeks after bringing her home, I wondered how other people kept their fish healthy (or at least alive). I had seen those tanks, filled with cheery schools swimming pertly around miniature castles. Was the life aquatic really so hard to weather? Of course, it isn't: Had I known then what I know now about putting together a fish tank, Maureen and I would have been in much better shape.

1 The tank

Start with a 10-gallon version -- fish-supply stores often sell them as part of a package that includes a filter, heater, light and thermometer (expect to pay about $65). Look for one with a three-way mechanical, biological and chemical box filter, which will clean debris, aerate the water and remove contaminants, as opposed to a simple mechanical filter that only cleans debris (if your package doesn't include such a filter, you can buy one separately). "If you spend more money on your filter, it's going to keep your tank a little healthier," says Victoria Hollifield, a veterinarian at Best Friends Veterinary Hospital in Rockville. "You won't have to do much cleaning."

2 The water

Tap water must be treated with a de-chlorinating solution before your fish can frolic freely. Water in the District and Fairfax County contains chloramines, a combination of chlorine and ammonia, requiring a different detoxification solution from the chlorinated water found in Maryland and other counties in Virginia, says Jay Wilkie of Congressional Aquarium in the District. Let your fish-supply seller know where you live.

3 The plants

Plants are a popular way to pretty up your tank, but those just starting out may find that live greenery is more trouble than it's worth. "Don't mess with the plants," advises Ken Yuen of Totally Fish in Aspen Hill. "If you're a beginner, you already have your hands full." Of course, plants do help oxygenate the tank, and they can make a tasty nibble for your fish, but if you're trying to choose between plastic and the real deal, keep in mind that a live plant is one more thing to, well, keep alive. If you do decide to go for it, green wisteria, anacharis and Amazon swords are all hardy specimens. Start with two or three; you can always add more later.

4 The fish

Certain breeds make particularly good starters. Guppies, mollies, Mickey Mouse moons, tetras, platys and swordtails come highly recommended: "They're undemanding about water conditions, they're easy to feed on food that is easy to get, and they stay small," says Andrew Blumhagen, president of the Potomac Valley Aquarium Society. Look for alert, active specimens, and make sure to buy from a reputable store (one of the reasons goldfish tend to die so quickly is that many are purchased at carnivals and carry common parasites, such as icks). Start with no more than 10 fish for a 10-gallon tank. One thing to know: These are all live-bearing species, meaning they will breed and give birth right in your tank. They tend to regulate their own numbers, but if this strikes you as problematic, you can buy only males; or, if your fish do breed and the tank gets crowded, many fish stores will gladly take excess offspring.

5 The food

Tropical flake food suits most fish just fine -- look for a brand that contains a combination of krill, algae, brine shrimp and bloodworms, all of which are favorites of omnivores. Sprinkle a tiny pinch over the tank twice a day, and scoop out uneaten food after about five minutes -- it'll just sink to the bottom of the tank and decompose, which means more frequent cleaning for you. Ronda Kaysen

Need some pet info? Drop a line to pets@washpost.com.