Black Koi is a koi fish variety.Here is more information about Black Koi.

black koi: knowing the fish better
there are also various species for the black koi breed. first is the magoi koi, the species which is one of the first all black mutations that can grow in really great lengths. they may look black when viewed from above, but in reality …

black koi: getting to know your fish a little better
the black koi differ from the other species due to their pattern and coloring, and nothing more. they can grow up to 36 inches long, that’s why there’s a need for them to be kept in large ponds. it can live up to 35 years old. …

Growing Black Koi Fish – The most beautiful fish among the Koi …
Black Koi is one of the most beautiful among the Koi fish varieties. The beauty of black koi can be very enchanting with its glamorous patterns of color.