Since not all snails and crabs like the same things I have a variety of them in my aquarium. My clean up crew consists of several blue and red legged hermit crabs, one emerald crab, two peppermint shrimp, one skunk cleaner shrimp, and a scattering of dwarf cerith snails, trochus snails, nassarius snails and astrea snails. My sand sifting diamond goby helps keep the sand clean.