Hello. I have the same kind of pleco.
You can read about the nitrogen cycle here
http://www.fishlore.com/NitrogenCycle.htm
Your pleco will poop ALOT ....I wouldnt reccomend any other fish in a 10 gallon with him and I would say if he is a baby he will outgrow that tank by himself in about 6 months, and that is pushing it. Not so much for size, but waste (poop)
When you see a piece of his poop laying around, suck it up with a turkey baster. If you do this everyday or two, it will go a long way in keeping the water quality good. In addition to regular water changes of course.
Hope that helps...they are nice plecos. He is my hubbys favourite fish, or else I probably would have returned the (not-so) little pooper for a smaller type.