A short article on the names of the color variations on koi, along with pictures. 
 
Koi is the general name for “carp” in Japanese. The name refers to all types of carp, from the simple dull gray fish to highly colored varieties.

The first fact you should know about Koi fish color meaning is that these colored varieties are called “nishikigoi” or “braided” carp.
The Japanese word can also mean love or affection, so these colored koi symbolize friendship and romantic love in Japan. 
 
Understanding Koi Fish Color Meaning | LifeDaily