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FISH / new pets

A Set-up Guide for Your New Fancy Goldfish

Tips for home and health

Overview

3 things to know about your new 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

Your fancy goldfish’s new home

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. Two adult goldfish will need at least a 29-gallon tank.
  • 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.
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What to put in your goldfish's tank

  • If you will be using an under-gravel filter, add it first.
  • Layer about 3 inches of gravel on the bottom of the tank. That works out to 1½ 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.
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Filtration

  • 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.
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Heat & lights

  • Goldfish prefer water temperature between 65 and 75 degrees Fahrenheit.
  • Choose an aquarium heater with 5 watts of power for each gallon of water in the aquarium. A large aquarium may need a heater at each end.
  • Wait 15 minutes after filling the tank before turning on the heater.
  • Place the heater close enough to the filter to distribute the warmed water.
  • Run the tank’s filter and the tank’s hood light for 24 hours, then check the water temperature and adjust the heater if necessary.
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Adding fancy goldfish to your 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. Try not to bring too much of their old water with them.
  • Add only three fish at a time to make sure the filter can handle all the new action in the neighborhood.
  • The chemical balance in your aquarium will change with every new fish you introduce, so check the tank’s pH, ammonia, nitrite and nitrate levels regularly.
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FREE Water quality testing

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

What to feed your 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.

Keeping 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
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General aquarium health guidelines

  • 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.

PETSMART CARES: 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.

The PetSmart Promise: 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.