The breeder is important information if you know something about the development tendencies of that breeder's fish. But too often, a highly regarded breeder's name leads to paying more for a fish than the quality deserves. Every breeder produces mediocre koi and "high level pond fish", as well as their "true show fish" and the rare "best quality koi". Lots of grades. The right approach is to buy the fish for its inate characteristics, rather than buying the breeder. Most folks, however, know the names of well-regarded breeders better than the traits of the koi they are observing. Whenever a person is planning to spend "their limit" on one koi, I think it is a good idea to get the advice and second opinions of others more knowledgeable. Koi Kichi are always happy to help spend other folks' money.
