The head is yellowish after coming out of a wild pond, but if kept in Sensui, Shiroji will become beautiful. Many Koi that are yellowish when they are young show their true potential of beautiful Shiroji. Shiroji becomes darker and thicker. Normally, we finish Koi at about 65cm, but since they have grown 6cm in 3 months in a wild pond, they still seem to grow, but since they are not that tall, it is better to finish them at 65cm. If Sumi comes out, he will be an excellent Koi.