Also called Japanese carp or nishikigoi, koi are temperate freshwater fish that can adapt to water temperatures of 47 to 95 degrees.
They are a domesticated variety of the common carp. Although both goldfish and koi share a common carp ancestor, goldfish are considered a separate species.
Male koi mature at 2 years and females at 4. Their average lifespan is 70 years.
Koi is Japanese for ‘carp.’ It is a homophone for the Japanese word for ‘affection’ or ‘love,’ and the fish are symbols of love and friendship.
There are 80 different varieties of koi, including variations, according to the International Nishikigoi Promotion Center, a Tokyobased group that is a resource for koi breeders.