I have a beautiful five-inch Plecostomus; he's gorgeous in color for a pleco with natural rusty spots on his fins and vibrant darker colors. He also has a huge dorsal fin (so he might be a sailfin, the petshop didn't say) which also adds to his looks. However, as of late, he has been getting teeny tiny perfectly round holes in it, and I don't know why. The only other fish in the aquarium with him are a few small feeder guppies and their fry. Does anybody have any idea what these holes might be from, or has anybody experienced the same thing? Despite the fact that I probably won't be able to keep him forever (unless he can find a place in my mother's fish pond) seeing as he will most likely reach 18 inches or more in length, I really like him, and want to know what might be wrong with him and whether or not I have something to worry about.