The name goldfish is misleading as not all fish of that breed are gold in color.
Some goldfish have patches of black or silver.
Despite common depiction of goldfish swimming in bowls, they should not be kept in such cramped containers. The limited space gives stress to your goldfish and eventually stunts their growth. A tank provides wider surface area for the goldfish to come up to the water surface to breathe. To prevent predators fishing into your tank, protect the opening with a secure cover.