One of my cherry barbs is looking to be in a really bad way

[THE99YEAROLDBARN]

I have a 23 litre fluval edge aquarium and in said aquarium I have 1 Male Betta fish, 2 Amano shrimp, 1 cherry shrimp, 6 neon tetras, and 4 cherry barbs. The cherry barbs in question has always had a bit of trouble swimming and I believe he probably has a problem with his swim bladder and because of that I frequently feed him and everyone else in the tank peas. This seems to improve him a bit and sometimes he swims normally like everyone else and sometimes he can barely swim at all like he is now. But just this morning I’ve noticed a red circle around a hole in his side and I’m really worried because I am thinking that it may be some sort of parasite that is burrowing into him and also I don’t have any other quarantine tank to put him in and I’m so worried also that the parasite (if there is one) will reproduce and burrow into the others. I also really don’t want him to die because I care about him a lot as I do for all my other fish. Also just for extra information the side of him with the hole in it is more swollen and bloated than the other as he is usually bloated anyway. I have tried to attach the best picture that I can get of him and his injury I hope that you can help me with it and could you please tell me whether it is just an injury or if it is something else. That would be really great and also although this is not the main problem that I have with him could you also possibly give me guidance on how to help him with his swim bladder issues as he’s had it ever since I got him but to be able to help him with that would be brilliant because I hate seeing him struggle.

[Martinspuddle]

Greetings.

Male Cherry Barbs can quite boisterous to one another, especially when there's a ripe female to be had. So this could of started as a territorial dispute and the wound has now festered into what looks like an ulcer. If you can catch the little blighter you could using a bowl of tank water, bath him in Melafix or Myxazin for 10 minutes for a few days.

Little fact that many don't know, in the wild Cherry Barb males are found singly and keep a harem of females in a close territory during spawning season.

[THE99YEAROLDBARN]

Thank you very much I shall try that, will it heal the wound?

[plankton]

It'll help reduce the chance of secondary infection and will sort of act as an antiseptic.

[Martinspuddle]

It'll help reduce the chance of secondary infection and will sort of act as an antiseptic.

@plankton you took the words right out of my mouth. In time, if there's no secondary infection it will heal.