Hermit Crabs are found on sandy areas surrounding reefs rather than moving about on them. These active creatures spend their time scavenging for food and make excellent partners in algae management. If added in large numbers, they will quickly rid the aquarium of algae and will move on to polyps, and other small animals. Will also steal food from sessile invertebrates. Diet Will eat filamentous algae and cyanobacteria. Feed meaty bits such as raw table shrimp, frozen mysis shrimp, silver sides, scallop, clam and mussel. They will appreciate offerings of Nori or other vegetation as well. Feed once or twice a week depending on amount of Hermit Crabs vs. amount of available food for them to forage on their own.