A koi's color cells sit at different depths in the skin, some right near the surface and some deeper in, which ultimately determines how bright the fish appears. The brighter the fish, the bigger ...

Koi carp are one of the most iconic ornamental fish in the world. Originally hailing from Japan, these beautiful fish have amazingly patterned bodies. There are many varieties–– and some of them are ...

Koi fish are what you might call a happy accident. In the 1600s, Japanese carp farmers began noticing unusual color variations among the fish. "The popular koi fish of today are actually ...