I have had a mata tang for 3 weeks now and he is a vicious eater. He was tank raised from a professional company and he looked great. Ever since I put him in he has had a block circles in different spots of his body and they turn into red spots (like ulcers). Idk what they are I've never seen anything like it. He has had them but still continues to act fine. I've been waiting it out but he still can't get rid of it please help!