Can a Comet Goldfish Live Happily in a 10 Gallon Tank?

Comet goldfish are a hardy, attractive goldfish often kept by beginner fish enthusiasts. These fish have elongated bodies and forked tail fins, and tend to be reddish or gold in color. Although comet goldfish are easy to keep, they still need some special care in order to remain healthy. Whether or not your goldfish can live in a 10 gallon tank depends on several factors.

  1. Fish Size

    • The size of the fish you're keeping is the biggest factor in determining whether an aquarium will be large enough. Comet goldfish can grow to anywhere between 4 and 12 inches long, depending on how much space they are provided with. Generally, in a large enough aquarium, these goldfish grow to between 7 and 8 inches, and will require between 20 and 30 gallons of water per fish. However, if the fish is young and still relatively small, a comet goldfish can be kept in a 10 gallon tank. The rule of thumb for young fish is to provide at least one gallon of water for every 1 inch of fish. Older fish need more than a gallon per inch. As the goldfish grows and ages it will require a larger aquarium. Although goldfish can grow to fit only the size of their aquarium, this stunts them and is detrimental to their health.

    Surface Area

    • All types of goldfish, including comet goldfish, require highly oxygenated water. Aquariums can be oxygenated using aerators, or with the aid of aquatic plants. Another factor in oxygenation is the amount of water at the surface of the aquarium, which directly receives oxygen. Some aquariums are shaped in such a way that the surface area is low, and don' provide enough oxygen. If you want to keep your comet goldfish in a 10 gallon aquarium, the surface area will need to be as large as possible. Choose a tank that is rectangular in shape.

    Water Cleanliness

    • Comet goldfish produce large amounts of waste material. In smaller aquarium this waste can quickly build up and deteriorate the water conditions. This can make the goldfish sick, and may even be fatal. When keeping fish in a smaller aquarium, be vigilant in keeping the water clean. Use a water filtration system. Make partial water changes, exchanging a quarter or a half of the dirty water in the tank with freshwater, at least once a week.

    Other Water Parameters

    • Comet goldfish prefer to live in water that is between 65 and 72 degrees Fahrenheit. The pH level of the water should be between 6 and 8. Abrupt changes in these levels can easily kill the fish. In a smaller aquarium, such as a 10 gallon one, water temperature and pH levels can be harder to maintain and balance. Check these levels often, even daily, when using a 10 gallon aquarium.