The fifth lesson in the Koi Expertise Course is about “Sumi”.
“Sumi” refers mainly to the black pattern in Showa Sanshoku (hereafter, Showa) and Taisho Sanshoku (hereafter, Sanke). Red, white, and black pattern of Showa or Sanke is composed of “Beni” (red), “Sumi” (black), and “Shiroji” (white). It is said that it is very difficult to produce Koi with good “Sumi”. This is because the “Sumi” of Koi when it is small and the “Sumi” after it has grown up give a very different impression.
Take a look at the picture below as an example.
The first picture shows that there is very little “Sumi” before it is put in the field pond. However, if you look at the second photo after growth, the “Sumi” is perfectly defined. The “Sumi” often appears as they grow, making it a very difficult point to discern their future potential. That is why the value of the Showa and Sanke periods, when “Sumi” was defined, is extremely high. Often “Sumi” disappears in Sanke. In the case of Sanke, “Sumi” on “Shiroji” between the “Beni” is one of the main elements that enhance the attractiveness of Koi, but the possibility of this exquisite “Sumi” disappearing is another difficulty of Sanke. The quality of “Sumi” also depends greatly on the growing environment (water quality, water temperature, etc.), so the individuality of the Koi farm can be clearly seen. Of course, it is a very profound and maniacal point in evaluating Koi, as it is greatly influenced by the parents.