I am currently intrigued by the idea of Peruvian apple snails for algae. They have a trap door so a bit of protection from predators.
The only thing holding me back atm is I have some big swords in there I don’t want the snail to eat.
Right now I have a larger sized L200 in my bass tank but it doesn’t seem to bother with the algae or any vegetables I put in the tank for it to eat. Just munches on said sword plants, and hopefully pellets. So I am planning to re home it to another tank once I lower the current bio load. It’s hard to find a pleco that actually eats algae. Smh. Lol