What would be considered a good amount/kind of food for him?

My pleco is likely a Pterygoplichthys pardalis or disjunctivus or a hybrid of the two. We've had him for about 6 years and when we got him he was only a few inches long and what we read about common plecos put us under the impression that he would only grow as large as the tank so we thought we were ...

Thank you both.The hybrid idea is interesting.

I have a common pleco and I'm trying to figure out what it might be. I thought it was either a Pterygoplichthys pardalis or disjunctivus but the ventral markings don't really seem be the definitive example of either to me.