Koi or more specifically nishikigoi, literally “brocaded carp”), are ornamental varieties of domesticated common carp (Cyprinus carpio) that are kept for decorative purposes in outdoor koi ponds or water gardens. Koi varieties are distinguished by coloration, patterning, and scalation. Some of the major colors are white, black, red, yellow, blue, and cream.
Koi are docile, social fish that enjoy living in pairs or groups. When considering whether or not to add a new fish to an existing habitat, always make sure that their environmental and nutritional requirements are the same as the current fish, and, in the case of adding a koi fish to an existing pond, make sure that the size of your pond is large enough to support a full-grown koi. Koi are truly friendly and will not eat other fish or fight with each other. If you are mixing species, make sure the same can be said for the other types of fish in your pond before adding koi. Not only are koi friendly to other fish, but they may also come up to the surface to say hello when they see their owner or when it’s time to eat. Some koi even like to be pet and will come to the surface for a little pat on the head.
