abcess?

[comet_nut]

I know this is going to sound excessively daft but is it possible for a blue chin trigger to get an abcess just below his lower jaw? When I puchased him he had been out of quarantine for about three weeks and looking extremly healthy. It took me a while to get him to eat, he is now feeding on a happy diet of raw prawn and squid. He has an open wound on his lower jaw that appeared about 4 days after I got him. I treated the tank with a week long course of melafix, then did a water change and another week long course to be on the safe side. It seemed to be healing but I looked at it the other day and it appears to have broken out again. The flesh that is healing is proud flesh (ie the flesh that is healing is outside the skin line, or should that be fin line?), so Im just wondering if this could be an abcess, I have seen the same sort of thing in my horse, I just wasnt sure if it was possibe to happen to a fish.
By the way he is in a 70 gal tank with about 50lbs of live rock. The water parametres are ammonia 0 nitrites 0 and nitrates 0, temp is 26'C and salinity is spot on. The lights are fluro and are on for about 9hrs a day. The tank has been up and running for about 3 months, and he is the only fish in there, aside from a few hermit crabs. I am currently running filtration through bio media and a skimmer. Other than the wound the fish is fit and healthy and very active. I have not been treating the tank now with melafix for about 4 days and the wound doesnt appeared to have changed.

 

[beth]

Sure fish can get absesses, tumors, cancer, etc., etc., just like any animal.
Is there any aggression going on in your system? Can you post up a picture??