Turbo snails don't really clean algea off rocks very good but they do a good job on the glass. I think the trochus snails (mexican snails) do a great job in cleaning algae off rocks, they are a bit more expensive than the turbos but they clean better IMO. For hair algea hermit crabs and emerald crabs do a great job. I think sally light foot crabs do too, For a 46 gal I would reccommend about 25 hermit crabs, 30 snails, sally light foot crab (if wanted). Also I had a cleaner shrimp that ate hair algea too.