Bichir Fish has a swelling on Side

Question
QUESTION: I have a bichir fish in a 55 gal tank. I have had it for appox. 6 mos. It's tank mates are all African Cichlids. There is no problem as far as getting along. Recently, my bichir deleloped a bumb on his side between his mid section and tail. It is starting to get larger. Is there anything I can do for him?
ANSWER: Hi Deborah
Is the bump internal or external?  If it's external, what color is it?

Christy

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QUESTION: Hi Christy,
It is internal and is starting to get a little red.

Answer
Hi Deborah
It's hard to diagnose fish diseases, so many symptoms mimic bacterial, parasitic, or protozoan infections-and of course all have different treatments...

Being the bump is internal, it could be a tumor-which there's no treatment for.  It could be an internal bacterial infection as well.  I would recommend trying an antibacterial food-that's the best way to get the antibiotics inside the fish.  The local petstores(here in the US anyway) usually sell it, it's a pellet food though, not sure if your fish is eating pellets or not.  If not, you could buy a regular pill or liquid antibiotic, you'll want one that is broad spectrum and treats gram negative bacterias(they'll say it on the bottle usually), and soak some of the fish's food in a small bowl of the antibiotic mixed with tank water.  

Hope that helps and good luck with treatment!  Let me know if you have more questions.

Christy