Plecos
I have two commons. They take care of my algae! My tank is SPOTLESS! I also have 2 otos they dont touch algae.. go figure.
depends what kind. Even though I love my plecos and they love eachother. They are messy, mean to other fish. Clyde (they big one) had killed a couple goldfish (never touched the faster dinos though). For a while i had a genious little albino pleco, the lfs ppl said that it would say under 4 inches or something, and wouldnt eat plants. unfortunatly it died.
SO What all that babbling ment was: I personally think pleco's rock, but dont get commons!*twirlysmi
EDIT:
Jk Clyde can catch the dinos, RIP