Why is there a wound on my plecostumus?
it could happen for many resons. It is possible he srcapped his nose on the gravel while looking for food. If you have another bottom feeder, especially another pleco, they fight somtimes. it is best to keep smooth natural type gravel or sand. But injuries can still happen, I would take out sharp objects and add a stress coat product like seachums para gaurd to help him heal, and continue adding it to new water, and anytime you add new fish, or handle/net a fish.