Floating fishie

Question
I have had a black moore fish for over seven years, when we originally got him i had never owned fish before, and got him, a algae eating fish, another moore, and a fighting fish and put them in my 20 gallon tank with a medium filter.  The petshop owners told me they were compatible, which turned out to be completely untrue.  The fighting fish killed my smaller black moore and bite the larger one, named pablo, creating a large gash on his side that eventually turned into a scar.  I removed the fighting fish, and for years Pablo was fine.  A little over a year ago, the area that had be torn began to swell, until it became a noticable growth.  He now has trouble swimming, and is often at the bottom or top of the tank, although he still does have many days when he swims normally.  I tried feeding him different things people suggested like peas and soaking my fish food in water before feeding it to him and his new black moore roommate (we got him a while AFTER Pablo became ill) but nothing worked.  I dont know what it is, or what to do about it.  I dont know whether it si a swim bladder infection, or a tumor, or sometihng else. Please help!
              Marie  

Answer
Hi Marie;

It could be a tumor or some kind of an internal infection causing an abcess. Make plenty of water changes like 25% every week while vacuuming the gravel. Even twice a week 25% changes isn't too much. If the tank is very clean and you don't overfeed, fish can often get through sicknesses on their own.

I rarely recommend traditional antibiotics, but if he doesn't improve in a week or two after a few cleanings, then I would try one. "Maracyn 2" by Mardel or "Kanacyn" by Aquatronics are the two main ones for internal infections. They actually get inside the fish, unlike most fish meds that treat only the outside of the fish. It would be best to isolate the fish to a separate "hospital tank" for treatment. Fish that aren't sick should not be getting treated too, and it can be much more expensive and risky to treat a larger tank. Make sure the hospital tank water gets changed frequently and it has an airstone hooked to an airpump for oxygen. You want a bare tank with no gravel or decorations and no filter. These things only absorb the medicine and keep it from helping the fish. It will also help the sick fish to rest away from others.

Followups welcome

At Your Service;
Chris Robbins

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