I have a small little common in the tank with my oscar amd I have noticed, that while the Oscar has NEVER picked on the little guy or even cared so much as to sniff at him, the tail on the pleco is lokking a bit messed up. It seems like it is splitting along the fin itself. My digital camera is broken, and I have no way of taking any pitcures of it for show. The water params all seem fine and not having any kind of issue with the oscar in there and both seem lively and very active.