What is your population, tank size, parameters like temperature ?
Amano shrimp, Red cherry shrimps, Siamensis Algea Eaters or Flying Fox (Very powerfull cleaner in big aquariums), Oto catfish...
I tried a gyrino for 3 month in a 10gal and it work well, then I selled it before he become agressive. Gyrino is very powerfull algae cleaner but requires very big tanks (100gal+)
Pleco aren't good cleaner IMO
and require 120gal+
Corydoras are stiring substrate, so you need to clean it less often, cause fish poop goes into filter instead substrate.