Breeder: Yamasan
Yamasan is a Niigata farm run by Manabu Yamazaki, working more than 50 mud ponds across something over 50,000 square metres, with upwards of 110 parent koi.
Yamasan's headline varieties are Hirenaga — longfin, or butterfly koi — and Hikarimono metallics including Lemon Hariwake. They also produce Gosanke, Shusui, Kujaku, Doitsu, Ginrin and Platinum, which makes it a broad-range farm rather than a single-variety specialist.
Butterfly koi are judged by a different standard from traditional nishikigoi — they are not shown at the All Japan, and no one pretends otherwise. The question with a good one is whether the fins carry: they should be long and even on both sides, trailing without looking ragged or thin, and the body underneath still has to be a proper koi body rather than an afterthought behind the finnage. A metallic platinum butterfly in open water is about as striking as a pond fish gets.
Yamasan koi available now
Everything here was imported by House of Koi. We chose almost every older koi individually at the farm, and those are one-of-a-kind: each listing carries video of that exact fish with its size, sex and year born, and closes when that fish sells. Tosai are bought both ways: we pick many out of the pond ourselves, and others come as a mix we chose at the farm, in which case the listing covers a group of young koi rather than one named fish.
Our Yamasan selection is all butterfly: Platinum Butterfly, Butterfly Platinum, a Butterfly Ginrin Yamabuki Ogon and Butterfly Yamabuki Ogon group, and a butterfly koi mix.
Live koi ship Tuesdays and Wednesdays, anywhere in the USA. Browse all available Japanese koi.
