Questions and issues regarding goldfish - one of the most popular aquarium fish. Use with other relevant tags, such as `feeding` or `health`

The tag should be used for questions regarding goldfish, include any other relevant tags, such as health.
Goldfish is cold water fish, a member of carp family and has been selectively bred for over a thousand of years, currently having a few hundred recognized varieties. Somewhat commonly they are seen erroneously as an easy-maintenance pet requiring a only a small, filterless bowl - while in fact they need from about 38 to 80 liters of tank volume per one specimen, depending on the variety, to thrive and be able to reach it's full potential lifespan of over 10 years.