I would label that one under the "Problem" category personally. Sorry didnt make myself clear all my fish in my 55 came down with some kind of wirling disease..where they swam in circles at the top of the tank, I lost a large male con a green terror then my jd got it. I finnaly cured it with perma & meta fix plus I used dip away. But I had no problem with aggression between the jd & gt.