A rubbernose pleco, also known as rubberlip or bulldog pleco should be ok. They only get to 4-5 inches in size. I just picked one up last Friday night and he has cleaned out my Eclipse System 12 gallon tank of algae and is now working on the algae on the ornaments. I have it in temporarily with my 2 fancy goldfish.
As for what kind of pleco you can house in your tank, let me go on record now as saying, any common pleco gets way too big. Bristle nose might be a better road to travel if your parameters are up to one.
I agree, I concur, I very well would've recommended this if I wasn't too late to the punch. I had a sturdy little fellow named Gorgon in a 20g, along with a community which perished during a viral-infected-LFS epidemic. The bristle nose was sturdy enough to be the only survivour, he was the perfect size for my large community of small fish. Or in your case, a small community of potentially large fish.
