The Kohaku is the most popular variety of Nishikigoi. So much so that there
is an expression, "Koi avocation begins and ends with Kohaku." There are various
tones of "red" color - red with thick crimson, light red, highly homogeneous
red, blurred red, and so on.
There are all sorts of "Kiwa (the edge of the pattern)" -scale-wide Kiwa,
razor-sharp Kiwa, and Kiwa resembling the edge of a torn blanket, etc.
Shades of white ground (skin) are quite diversified too -- skin with soft
shade of fresh-unshelled, hardboiled egg, skin with hard shade of porcelain,
yellowish skin, and so forth.