Yamanaka Oya
Yamanaka Oya breeds Shiro Utsuri, Go-Sanke, Hariwake, Midori, Ai Goromo, Hikarimono and Aya Wakaba. Aya Wakaba, which means "coloured young leaf" in Japanese, is basically a Midori koi, with pattern instead of uniform colouration. Oya San breeds approx. 10,000 tosai and raises 1,500 nisai each year.
