The size of a goldfish's tank partially determines adult size, and many goldfish grow quickly to more than 10 inches. Goldfish thrive in larger aquariums because they can swim freely. Transferring your goldfish to a larger tank is easy and will greatly benefit your fish.
Set up the new tank before transferring your fish. The water conditions in the new tank should be the same as those in the old tank, unless the old tank was an improper temperature or pH. Use a dechlorinating agent (sold at most pet stores) to remove chlorine from the new tank, and ensure the temperature is between 65 and 72 degrees Fahrenheit. Adding aquarium water from the old tank to the new tank can help stabilize conditions so that your fish don't suffer from transfer shock.
Provide a few extra hiding places, such as plants or aquarium ornaments, in the new tank. These give your fish places to hide as they adjust to their new, more spacious surroundings.
Use a fishnet to catch your fish. The net should be at least double the size of your largest fish. Scoop them into the net one at a time. Cover the top of the net with your hand to ensure the fish do not jump out. Place the net in the new aquarium and allow the fish to swim out on their own.
- Complete Goldfish Care: Your First Goldfish Tank: Which Is the Better Option?
- Aquarium Care of Goldfish; David E. Boruchowitz
Brenna Davis is a professional writer who covers parenting, pets, health and legal topics. Her articles have appeared in a variety of newspapers and magazines as well as on websites. She is a court-appointed special advocate and is certified in crisis counseling and child and infant nutrition. She holds degrees in developmental psychology and philosophy from Georgia State University.