Just scrub it off it you have unwanted algae.
I have an apple snail and an oto in my tank, and the algae on the sides makes it kinda hard to see in the tank sometime, but I took the scrubber off because I am essentially farming the algae for them to eat, so my oto will get fat and happy. My point is, I have algae because I have things that eat it, not the other way around. Livestock is actually pretty terrible at tank care, so if you don't want the algae, reduce your light time, put in more plants, or just scrub it off. :thm:
Plecos don't eat algae so well. They will if they are starving, but they don't get to be 2 ft in the Amazon by eating algae! They actually have a rather complex and varied diet.