CLEANER SHRIMP: You are looking at an underwater cleaning station — a living, breathing bathtub for filthy fish. These pint-sized creatures, called cleaner shrimp, live on tiny, parasitic crustaceans and dead skin, which tend to accumulate on fish over time. Tiny, parasitic crustaceans are like the insects of the sea, and are just as irritating for fish as insects are for us. So for dirty fish, cleaner shrimp are godsends. Cleaner shrimp dance to advertise their services, rocking back and forth to a hidden beat or tapdancing on their spindly legs, depending on the species. This attracts an orderly queue of fish, which may include such fearsome predators as sharks and moray eels. Several shrimp will clean a single fish at a time, scuttling over its entire body and even prying parasites out of the fish's open mouth. Because they're so valuable to the reef community, these shrimp tend to be left alone during cleaning interactions.