Germans use carp as a food source. A carp without scales was considered expedient for cleaning, so the Germans developed a carp with minimal scales. The Japanese crossed the German carp with their Wagoi wh :ich resulted in Doitsu Koi. There are three basic varieties of Doitsu Koi, Mirror, Leather, and Armor scale arrangements. Mirror scale Koi have four rows of scales, two along the lateral line on each side and two on each side of the dorsal fin. The leather Koi definition varies a bit, such as two full rows on each side of the dorsal fin, or two partial rows on each side of the dorsal, or no scales at all. Then there is the undesirable armor scale with very large scales scattered in total disarray over the body of the fish. The proper terms for the two desirable types are Kagami-goi (mirror carp) and Kawas-goi (leather carp).
It would be proper to say "mirror doitsu koi" or "mirror doitsu goi" and "leather doitsu koi" or "leather doitsu goi" goi being another Japanese word for carp. Hope this helps.
Paul
