Weird story here, so I finally got my reef going. About a year old, tons of coral, cleanup crew, a cleaner shrimp, and even a few fish. Anyway the fish I have are a snowflake clown, a purple fire fish, and a red firefish, and a yellow banded possum wrasse. My possum looked great and fat and loved to actually be seen. He wasn't shy and he was still super sweet to other fish. Well I've noticed some aggression from my purple firefish as odd as it is. It bit my clowns tail off (the clown is only 3/4 of an inch) anyway the possum wasn't acting itself for a couple days and I didn't have high hopes for it. I found it dead this afternoon and when I took him out I found a huge gash that shows his meat. I assumed I just must've scraped him on a rock on the way out. I checked my parameters ASAP and everything was normal and super clean. It makes me think that the gash was from the firefish. Anyway if I am right it would be impossible to get the firefish out. Should I go with more semi aggressive type fish? Any suggestions would be helpful