Yamacho Koi Farm, also known as Chogoro Koi Farm – is run by Nobuaki Hiroi in the Kawaguchi region. Established more than 30 years ago, they have become world famous for their Platinum Ogon (Purachina). If you are looking for a Platinum Ogon, or Ginrin Plantinum Ogon, then you’ll want to find one from Chogoro. They also breed other varieties such as Goshiki, Gin Matsuba and Kikokuryu.