Care guide

Caring for aquarium fish, shrimp and snails

Healthy aquatic animals start with healthy water. Set up and cycle the tank before anything arrives, match the water the seller keeps them in, and change part of the water every week.

Cycle the tank first

A new tank needs about four to six weeks to grow the bacteria that turn waste into less harmful forms. This is called cycling. Test for ammonia, nitrite and nitrate; the tank is ready when ammonia and nitrite read zero and nitrate is present.

Adding animals to an uncycled tank is the most common reason new fish and shrimp die. A filter, heater (for tropical species), lid and a water conditioner that removes chlorine and chloramine are the basics.

Match the water

Ask the seller what they keep the animals in: temperature, pH and hardness (GH and KH). Sudden changes stress them, so aim for the same range at home.

Change about 10 to 25 percent of the water each week, using conditioned water at the same temperature. Test the water regularly, and more often if something seems off.

When they arrive

Float the closed bag in the tank for 15 to 20 minutes so the temperatures match. For shrimp and sensitive fish, drip a little tank water into a container with them over 30 to 60 minutes before moving them in.

Keep the lights low for the first day. Don't add the water from the bag to your tank.

If you can, quarantine new arrivals in a separate tank for a few weeks before they join others. It keeps disease from spreading.

Feeding

Feed small amounts that are eaten within a couple of minutes, once or twice a day. Uneaten food fouls the water quickly. Shrimp and snails also graze on the film that grows on surfaces, so many need only light feeding.

Signs to watch for

Gasping at the surface, clamped fins, white spots, rubbing against objects, or not eating can all mean a problem. Check the water first; most problems start there.

An aquatic vet or an experienced local fish store can help. Never release aquarium animals or plants into ponds, lakes or rivers.