Nassarius snails [sand stirring]
Hermit Crabs (Scarlet or blue leg)
Emerald Crabs [bubble and hair algae]
Cleaner Shrimp [makes sure everything is copastetic on your fish/inverts]
Peppermint Shrimp [Aipstasia, also fallen foods... etc]
Turbo Snails [diatom algae]