Red bubble coming our of fish, around his butt

[nuzzler]

Hi, my favourite fish VC has had a bubble coming out of him for a few weeks now and it seems to be very slowly getting bigger. Water parameters are fine, other fish are not bothering him from what I can see, and he moves around like normal and has a healthy appetite. I did fast the whole tank for 3 days to see if he was constipated but it didn't change anything. I am worried that it is something serious as it looks bad to me. Can anyone help me identify what the issue is?

 

[Rocksor]

Could be results of an injury. If he is in quarantine, you can add epsom salt to tank, which will help to reduce the swelling. Add about 1 tablepsoon per 5 gallons for a total of 3 days.

 

[A201]

The growth might be Lymphocystis, a non lethal viral growth. It's comparable to a cold sore.

 

[nuzzler]

Okay, thanks for the responses, if no one thinks it is a bacteria or something then I guess I will just leave him be and hope one day he heals.