In some Chinese or Japanese households, one may find a pond in the backyard filled with koi, one of the most popular pond fish. How did the Koi Get it's colour? Koi Carps are actually a colour mutation of the classic common carp, originally a dull, . Pez Koi Real, Tropical Fish Pictures, Koi Fish Colors, Butterfly Koi, Koi Fish Pond, Fish Fish, Coy Pond, Pond Water Features, Pond Design