| Reading an old Japanese koi magazine, I came across a comment I've not heard before. It was stated that Asagi and Shusui turn dark when there is high iron content in water. There was an implication that it may be iron content rather than hardness that affects darkening in Asagi. Of course, hard water can have a high iron content. As so often occurs in translation from Japanese, the meaning is not as clear as one would like. |