Hi, I have my flowerhorn Paul for about 2 months ago, occasionally I do 48-72 hours at work in one go so have to leave him. I installed an automatic feeder for this time. I have noticed recently that when I come back he looks like he is covered in grazes. First time was his side and this time was all over his kok? He shares at 270 litre tank for the time being with clown loach who stay away from him. His is about 3 inches. Parameters are 0 ammonia, 0 nitrite and 40 nitrate. Am about to do at 60% water change but wondering if this is a disease or him bashing himself on something?