I don't think so, unless it's internal and HUGE. I haven't dealt much with fish parasites though, excepting Ich and those that present in poop haha.
He's falling off to the side now when he's laying on the bottom of his cup. I'm going to try to upload another photo so you can see it better. It's light brown like a pellet, but when I was looking at it, there was no physical distinction between its edges and the edges of his gills, which are the dark red-brown.
Whatever it is, it and I are wearing him out fast. Should I put him in salt to help drain it if it is an abscess?
I believe it started tonight, but I'm not 100% on that. I was out of the house all day today at work, and when I got home I cupped him and fed him, which makes him huff and puff. He huffs and puffs a lot anyway, he's just that kind of guy.
What would a gill fluke look like? If this is a parasite, it's IN his gills.
It would move, for one thing. Beyond that, I'm not sure. This is supposedly what it would look like. But if the distress only just started, I'm thinking it's probably not that. He would have had a lot of them and the respiratory distress would have started a while ago. Probably along with rubbing and darting.
EDIT: Go ahead and put him in 1 tsp of AQ salt per gallon with any Stress Coat to stabilize and calm him down. Maybe leave him like that for a day or so.
If it's an internal abscess, then we'll want to switch him to epsom salt once he's built back up some slime coat. But I'm not sure. The epsom salt will reduce the swelling but I'm not sure it will drain the actual fluid out. Only popping the abscess would do that and if that happens, we run the risk of infection.
I don't think that's what's going on here. Though symptom-wise, it would be hard to say. He's just a fusspot! He has always darted, rubbed, tail-bitten, all that stuff. He shares a divided tank though, so I suspect if it were something in the water, I'd see symptoms in the boy in the other side, and he's perfectly fine.
That I will do. Is he better off in his cup floating in the heated tank, or should I leave him out and cover the cup so it's dark?
If he's having trouble breathing, it's probably best to keep him floating in his cup so he's closer to the surface. I also went ahead and PMed DarkMoon17 about this so hopefully she can chime in with her veterinary experience. I hope the little fellow does okay through the night.