Mt lacetail guppy has been laying on the bottom of the tank for about 2 days, still beathing and moving its fins but not moving around at all. It's tail is all bunched up and there is a yellow sploch at the beggining of his tail.(not sure if it was already there. Any ideas whats wrong? i tested my water and everything was fine and ammonia was .08, so anyone know? Any ideas on curing it or what?