What do you mean you're "getting a pleco?"
Most of them get really huge (1 foot sometimes.) And I hear they are poop machines.
I think there's a couple that stay smaller, like bristlenoses.
Wait around for more opinions because I'm not sure about this.
If you want something that will eat algae when it appears, I'd go with otos depending on what else you've got in the tank and how big it is.
Btw, you can post all your tanks and stuff in your signature like mine.