Koshiji Koi Farm (Kase)

Kiyoshi Kase is the Niigata breeder you go to for new varieties. His Koshiji Koi Farm, in Iwata in the Koshiji district of Nagaoka, created Ginga (Kujaku crossed with Hajiro) and Beni Kumonryu (a Kumonryu carrying red, made by first crossing Doitsu Showa into the line and then Kikusui), and he has spent over fifty years stabilising metallic and Doitsu types: Kikokuryu, Kikusui, Yamato Nishiki, Doitsu Gosanke. The Nishikigoi Promotion Center's summary was that his ponds are always full of colour.

Kase was a sushi chef first. He started keeping koi as a hobby at 20 and set up the farm in 1969 at 25. Much of the new-variety work was done jointly with Aoki Koi Farm; the two breeders raise each other's fish so that a disaster at one farm cannot wipe out a line, and Aoki, not Kase, gets the credit for Kin Kikokuryu. The farm runs about 7 hectares of hill land with 50 mud ponds, around 100 parent koi and roughly 20,000 koi a year, most of it exported. ChampKoi lists these fish under the vendor name Kase.

Two buying notes. His Showa are no sideline: a Koshiji Showa won its division, the Niigata Governor's Prize and the Niigata Nishikigoi Council Chairman's Prize at the 59th Niigata Prefecture Nishikigoi Show in October 2019. And if you buy a young Kikokuryu from him expecting a finished look, read this first. Kase keeps the Kikokuryu fry that are solid black at 40 days, because the pattern is hiding under the sumi and emerges as the fish grows, sometimes at tosai, sometimes at two or three years. That is the fun of the variety, and the reason a plain-looking Kikokuryu tosai can be a good buy.

ChampKoi imports koi from Koshiji Koi Farm.