Did a dumb thing. Was in a rush and bought a BN pleco without really looking at it. Put it in my tank without quarantining it like an idiot. 2 days later it comes out of hiding and I see this. I don’t have a spare tank to put it in so what do I do now?
Can you take a pic with him on the glass so we can see his belly? It looks a bit like he is emaciated, at which point I think you should try to return him.
If he gets on the glass I will take a pic. I can’t return him as LFS is an hour drive. Would cost more in gas than I would get back. I’m just pissed at myself because I know better. I trust this shop because they are good about quarantine if they see an issue.
I hate doing remote diagnosis. In fact I hate doiong it even in person. That said, I believe you are dealing with two issues. The first, and less serious, would be fin rot. It looks bacterial but i cannot say for sure. The second issues, again if a am correct, would be columnaris aka mouth fungus or saddleback disease. This is also bacteria and for sure requires real antibiotics to cure. One more note on this illness, There are a variety of strains of the disease which are more or less virulwnt. The worst forms can wipe out a tank faorly quickly while milder infections can persist for a long time without many fatalities. Hobbyists cannot tell which strain mmay be affecting them until they see the fish with symptoms and starting to die.
Because you can see your fish and the symptoms clearly, I suggest you research these two problems and try to confir what I suspect. Please do not assume I am correct ir wrong without doing your own independent confirmation.
Here is a research paper that is above my pay grade, but it can provide you with better info than you are likely to find on most fish sites. You should be able to undersatnd the key points if you stay away from the more scientific terms and parts. Columnaris disease in fish: a review with emphasis on bacterium-host interactions
Daisy I'm sorry about your bristlenose. They are they guppy amongst catfishes though, if you want another just look locally in your area on Craigslist or something, usually people have so many fry they have trouble selling them for a dollar, or even giving them away.
It is also very unlikely you will have such problems with fish from local breeders or hobbyists.
I'm sorry too, Daisy. Without other fish in the tank, I would do several 90+% water changes & WAIT to get new fish. Hopefully, the disease, whatever it was, will burn itself out without a host.