breeding

Question
I have a large plecostomus and a large catfish no understand that pleco is a catfish also and they have been playful lately was. Wondering if they can mate or breed.

Answer
Hello,
They are of different genus and therefore cannot breed.
I would take that behavior as a warning though, with catfish seemingly playful behaviour is actually the early stages of territorial aggression. You might want to consider separating them before things get violent and they hurt eachother as well as their tank mates.