This small crab is the best algae eating hermit crab we have tested.

Chibanarius digueti feeds on algae that grows on the rocky substrate and mangrove roots. C. digueti occupies a large variety of shells. This hermit crab is found in the oldest coraline incrusted shells. I have found entire colonies in broken sand worn shells. The crabs from La paz often occupied such a strange assortment of shells that I could identify the colonies before I looked at the crabs.
Both the Blue leg hermits and the red San Sabastion crabs always are collected in clean fresh shells. Both of these crabs have eaten snails in my reef tanks. I have kept C. digurti in reef tanks in colonies of over 10 crabs per gallon with many types of snails.

These red legged crabs are very effective at eating hair algae. I have observed many small C. digueti settle in the center of patches of hair algae and stay there for several days until they have cleared a patch over one inch in diameter. This small hermit crab will clean red sponges and small polyp colonies and not damage them in any way. I have watched these crabs clean red cyanabacteria from new woods polyps and not damage the cuttings. In nature C. digueti feeds by scavenging the algae that has started to decay from being exposed at low tide. I often find large groups of these hermit crabs on algae covered rocks.s