hey bud, welcome.
get some pics happening if you can. your tank might be looking like a tin of sardines at this point, although benifical to have rockwork, it just sounded like alot of rockwork for a small tank. sorry to hear about your fish, did you return him after all that, or is he still in the
QT?
How long have you had the main tank set-up? If its new the fish might be responding with aggression compounded by this. Although unless bonded, your asking for war to begin with i guess.