Article Hero Image

FISH / new pets

Fancy Goldfish Care Guide

Tips from home to health to food and fun


3 things to know about your fancy goldfish

  • They can live from 10 to 30 years
  • They can grow up to a foot long
  • They should live only with other fancy goldfish

How do I set up an aquarium for my fancy goldfish?

Set up the aquarium at least one day before you add any fish.

Aquarium and stand

  • The minimum size of your aquarium depends on how many fancy goldfish you have and how big they will be as adults. You should have 20 gallons of water per fancy goldfish.
  • The aquarium should be near a power source in a low-traffic area, away from direct sunlight and drafts.
  • Water weighs 8 pounds per gallon. Pick a very sturdy, stable base for your aquarium, then fill the tank with dechlorinated water.
Shop aquarium starter kits Shop aquarium stands

What to put in your goldfish's tank

  • Layer about 2 inches of gravel on the bottom of the tank. That works out to 1 pounds of gravel per gallon of water. Rinse the gravel before putting it in the aquarium.
  • Fill the tank about halfway up with dechlorinated water.
  • Add the thermometer and other necessary equipment.
  • Time to decorate! Add fish furniture, rocks and plants. Because fancy goldfish might eat live plants, it’s best to use fake ones. Rinse all décor before adding it to the tank.
  • Finish by filling the tank the rest of the way with dechlorinated water.
Shop décor, gravel & substrate Shop thermometers Shop aquarium cycling aids Shop bacteria-fighting aquarium supplements


  • An aquarium filter should be able to process all of the water in the tank three to five times an hour. For example, the filter in a 20-gallon tank would need to push through at least 60 gallons of water each hour. Follow the manufacturer’s instructions for choosing and setting up the filter.

Run the tank’s filter and the tank’s hood light for 24 hours.

Shop aquarium filters Shop aquarium lighting


  • Goldfish prefer water temperature between 65 and 75 degrees Fahrenheit.

How do I add fancy goldfish to my aquarium?

  • Bring your fancy goldfish home right away after you buy them.
  • Place them in your aquarium — inside their bag — for 15 minutes so they can get used to the new water temperature.
  • Next, use a net to transfer the goldfish into your aquarium. Do not add any bag water to your aquarium.
  • Add one or two fish at a time to make sure the filter can handle all the waste produced by the new fish.
  • The chemical balance in your aquarium will change with every new fish you introduce, so check the tank’s ammonia, nitrite and nitrate levels regularly.
Shop aquarium test kits

FREE Water quality testing

PetSmart offers free aquarium water testing. Bring in a sample and we can test its quality within minutes.

What do I feed my fancy goldfish?

Goldfish eat flake food or pellets. To reduce the risk of buoyancy disorders caused when fish gulp air at the water surface, feed your goldfish sinking pellets, or place the flake food under the surface of the water when feeding. Make sure to get fish food formulated for goldfish.

Shop goldfish flakes

How can I keep my fancy goldfish healthy?

If your fancy goldfish display any of these symptoms of illness or distress, talk to a PetSmart store associate or a veterinarian familiar with fish health:

  • Decreased appetite
  • Fins clamped to the sides
  • Scraping body on rocks
  • Abdominal swelling
  • Inflamed or discolored skin or fins


  • Fish and aquatic animals can transmit disease to humans. Wash your hands with soap and water before and after interacting with your aquarium. Children, pregnant women, elderly people and people with immune-system problems should take extra care.
  • Keep fish away from food and areas where food is prepared.
  • Never release fish into the wild.
  • Adults should assist children with hand washing after contact with a pet, its habitat or aquarium water.
  • Always add dechlorinator or water conditioner to tap water before adding it to the aquarium.
  • Do not use soaps or detergents to clean aquarium or décor, since they are toxic to fish.


Pets purchased at PetSmart are part of our exclusive Vet Assured program, designed by PetSmart veterinarians to help improve the health and well being of our pets.

Our vendors meet a high standard in caring for pets and screening them for common illnesses. This program also includes specific standards for in-store pet care.


If your pet becomes ill during the initial 14-day period, or if you’re not satisfied for any reason, PetSmart will gladly replace the pet or refund the purchase price.