About 50 years ago, there was Kohaku called "Tomoin" in Takezawa, Niigata. The bloodline of Tomoin dominated the market for the time because its Hi was truly blood red. Mr. Kiyoshi Miyazaki spent a large sum of money to get a pair of this Tomoin Kohaku. From his breeding, he produced two outstanding pairs of Kohaku.
In 1967, Mr. Kinsaku Hoshino spent large money at the annual gross sale to get the two pairs from Mr. Miyazaki. They were almost 70cm long (28 in") and considered very big at that time. With the four parents, there were four possible pairs. He decided upon one pair out of the four. That pair is what is called "Sanganmatsu," is the origin of Hoshikin Kohaku.
Descendants of this bloodline won grand champions two times at Nogyosai; Niigata Koi Show, All Japan Young Nishikigoi show, and more. Hoshikin Kohaku is now a representative bloodline of Kohaku.
Niigata breeds excellent quality Koi because all the 200 breeders have had clear visions of what kind of Koi they want to breed and improved their Koi to meet their goals just like Mr. Hoshino has done.
The goals of Hoshikin now are to create 1) strong Koi resistant to disease, 2) Koi that grows large and 3) Koi that holds their beauty at hobbyists' ponds.
Pursuing for these goals, he breeds 3 million fry with 10 pairs of Kohaku every year. He releases them into 2.5 acres mud ponds and culls them three times from July to October, choosing 15000 fry. From these, he keeps only 1000 Koi to raise to 2 years old and sell the rest. In other words, only 14000 Hoshikin Kohaku are available in a year. It is a very limited brand. Japan has many fans of the Hoshikin Kohaku, especially high end oriented hobbyists