my pleco was trying to swim and one of my cons was nudging him wiith his head and the next time i looked at my tank my pleco was kind of chasing my con. he wasn't chasing him around the tank, but he was just following the con like he was challenging him, and the con was moving in a cricle like he was trying to avoid him... has anyone ever noticed this? ive heard of plecos eating slime off of fish, but i have never seem mine do it, so i dont think thats what was happening... oh yeah, his dorsal fin was erect too.