If you go to your local Pet store, Check out The African tanks. Just look at them for a few minutes. I will be surprised if you tell me none of the fish are scratching / flashing. Anyway if you do see this, I would really like to know what is going on----- For years I can't figure this out. Again there is no signs of Ich. Some one must know what this is. I am at the point now to seek out the answer.