Cory cat issue

[ChrisUSArmy]

Later I noticed my Emerald green Cory cat has developed sore/hole on his right side just below the front of his dorsal fin. This appears to be getting larger slowly and I’m concerned for him. I need some solid help as I suspect this is a bacterial infection.

 

[GaryE]

Ouch. It appears he has been badly bitten by something, and the wound is well infected. Hopefully, someone from your region can check in a say what possible meds are available to you.

 

[ChrisUSArmy]

Yes, I agree it does looks like a bite as well. There are not too many fish in the that I could seriously point a finger at, especially since I keep the tank well fed (1 good healthy feeding early evening) daily. Possible perps below
Red tail black shark 3 inches
Silver dollar ( actual silver dollar size)

 

[GaryE]

I would put an investigative team to follow the red tailed shark, especially at night when they're known to attack tankmates. They don't all do it, but a lot of them do. They're not fish I would have in the same tank as a Cory. They share the same niche, and so compete, and one of them is known to kill tankmates.