My dominant discus died this morning/last night, I had 3 discus in the tank all relatively young and small, one of them grew a lot quicker then the other two becoming already an inch bigger then the other two I thought that maybe it was just because she got a little more of the food an a bit more aggressive but I've woken up this morning to find her dead under some driftwood and just wondered if they was an explanation for this as the rest of my tank seems very happy still.