It then carries the protective shell on its back. When hermit crabs outgrow their current shell, they must find another one. A hermit crab goes through its own little ritual when it does find a better shell. First, it inspects the new shell, touching and grasping it, and turning it until it can inspect the opening with its antennae. If it likes what it finds, it quickly moves in, sometimes changing just as quickly back to their original shell.
Some hermit crabs have anemones attached to their shells.
As the hermit crab eats, scraps of food float away which the anemone eats. In turn, the anemone provides protection for the hermit crab. When a crab changes shells, it may even place its anemones on the new crab. Most arthropods are scavengers, eating just about anything and everything that settles to the ocean floor. Skeleton shrimp feed detritus, algae or animals.