The common goldfish is a breed of goldfish and a family of Cyprinidae of order cypriniforms.Goldfish are a form of domesticated wild carp and are a close relative of koi. Most varieties of fancy goldfish were derived from this simple breed. Common goldfish come in a variety of colors including red, orange, red/white, white/black, yellow/white, blue, grey/brown, olive green, yellow, white, and black, with the most common variation being orange, hence the name. Sometimes, the brightness, duration, and vividness of the color may be an indication of the fish's health status, but not always , as manifold waters conditions facilitate the apparent discoloration.