Could also have developed a taste for slime coat, and scales. Plecos can wreak havok on a cichlid tank. When you shut the light off the plecos come out and the cichlids go to sleep. When cichlids sleep they pretty much all just huddle on the bottom. Usually totally oblivious to a pleco sucking away on them. If you start to notice hickies on your fish take it out! My L001 does the same thing to my malawi peacocks. It's about 10" and it doesn't hurt the cichlid when it rams them. Their usually pretty good about evading the blow. Just watch out for the odontodes. If they corner the fish they will try to smash it with their body, pectoral, and facial odontodes. If I reach my hand into my big pseudo's cave it will smash my hand against the side of the cave with all the force it can give. I'll tell you right now it hurts like hell. Especially because my pseudo is covered with spikes from head to tail.