This morning I noticed that my pleco has a small hole in one of its fins. I am curious as to what might have caused this. It also sort of looks almost like someone blew charcoal dust on its fins, though this is probably just coloration I hadn't taken note of before.

Still, I was wondering if this might be some disease I am unfamiliar with.

My pleco also has a few tiny holes at the base of the dorsal fin. I don't know what caused it, perhaps a physical injury at some point. It doesn't seem to bother my pleco. As long as the edges of the hole aren't fuzzy, white, gray, or otherwise abnormal, it's probably not a disease that you have worry about.

I'm not sure about the "charcoal dust" to which you refer. Are there little black spots all over that weren't there before? There is a disease called black spot but it's not all that common (requires snails as intermediate hosts). I hope it's just coloration you didn't notice before as you said.

I am guessing it is just coloration. I don't often get a really good look at its fins after all, and the thing is growing up in a hurry. Oddly enough it still has that red on its fins.

I am starting to wonder if that is just coloration as well, as none of the treatments I have used have put a dent in it, and I figure if it really was blood poisoning, my pleco would have died... or at least look weak or something.

it may be a different type of pleco or something.