large fish ulcer

Question
Hi Tina,

I have a tetra (bleeding heart) that has developed a large ulcer/lesion on its back, behind its dorsal fin. When it appeared that this wasn't healing on its own (at this stage it was getting deeper and started turning reddish/bloody) I moved the fish to a hospital tank and began treating with erythromycin tablets for 4 days as indicated, along with Melafix.  I've continued treating with Melafix, and am on day 5 of treatment.  Also doing 30% water changes daily, using water from the original tank, in which all the other fish are healthy and thriving.  This water also contains a low level of salt.  The ulcer is now a whitish colour, and I am not sure if it is healing or progressing deeper into the tissue.  Is there a way to tell if the fish is improving, or if it should be euthanized?  It is acting normally otherwise.  How long should I continue treatment before giving up hope that this fish will recover?  Thanks for any help you can offer.

Answer
Kim,                                                         You didn't say how long you had him. If it is going away he is improving. I would have treated him with tetracycline. Unfortunately they can suffer from the same things we do cancer and such..... I know how attached we get to our babies. There really is no giving up.... you just do the best you can. I don't think what he has is infectious..... I would put him back in the tank give it 2 days then try tetracycline. Take your carbon out treat 7 days.... no matter what it says no water changes....then a 25%. If he don't come back he may be old or have a cancer or something .... let him go at home peacefully..... Let me know what happens please...Good Luck......Tina