I've had good luck with gold dust plecos in the genus Baryancistrus (e.g., L018, L081, L200). I'd avoid the wood eaters like Panaque species (Royal Plecos) because they are incredible poop machines. I had a 4" Panaque sp in a 100 gallon tank and it clogged the filters weekly. After I removed it, the load on the filters went down dramatically. You won't have the same problem with species that feed mainly on algae. I've had no problem keeping Baryancistrus with centrals.