Bloodfin Tetra, White Patches, Acting Vaguely Lethargic

Alright, noticed that one of my larger bloodfin tetras has three white patches on him. He isn't contorted in any way. The patches are a bit fuzzy, almost as if they're scrapes rather than just discolorations. I initially thought he had injured himself but because the patches are numerous I don't suspect this anymore. He has a patch on each side set back from the gills and then another on top before his dorsal fin. He may be a bit lethargic though I think that's from me terrorising him with the net as I tried to catch him. I've separated him from my other 8 blood fins. I may have noticed him acting slightly weird this morning, swimming along the surface mouthing at particles, I thought he was just foraging for leftover food but with this disease I'm not entirely sure if it's a symptom or just normal behavior. I've got plenty of petcos and petsmarts around me so I can get meds, though I do have mystery snails. I suspect its columnaris, or false neon tetra disease. No other fish are showing symptoms and they all appear healthy.

I've attached photos. The patches aren't huge but are definitely there. They stand out even on the pale color of the bloodfin.

Thanks for any help!

 

I'm working on a quarantine tank for him now

 

Ammonia 0ppm, Nitrites 0ppm, nitrates 5ppm

Hes now in quarantine but doing very poorly, I don't know if the stress of being netted is the cause, it shouldn't be shock as it's his own tanks water, but he is doing very badly now

 

Turns out it is another bloodfin thar was swimming around at the surface, hes doing it again now. The wounded or infected bloodfin in quarantine seems stable but is just sort of listless and hovering at the bottom, I can't find anything that matches the description of his issues. The wounds don't seem fuzzy as fungus would, only very slightly. It looks mostly like he scraped himself on something, but I find it hard to believe that he would scrape his sides and the top of his head all in one go.

 

He's swimming is slow circles this morning, I should probably euthanize him, I can't figure out what this would be