Cucs aren't necessary. They do help a bit, but arent needed. Starfish (brittle stars NOT green brittles and serpent stars are good) snails, hermits, and IMO, conchs are very good. Also, I have heard that cucumbers can be awesome at cleaning sand. Nassarius snails , hermits, starfish for uneaten food, turbo or Astraea snails for algae. The conch or cucumber will help with detritus.