The skunk cleaner shrimp is an extraordinarily versatile little shrimp that is perfect for most reef tanks, and also for many fish-only tanks without fish that pose a predatory risk to crustaceans. They are omnivorous scavengers, eating almost anything, but are most-well known for their symbiotic relationship with many fish. When a fish comes down with Ich or another type of skin infection, it will sidle up next to the shrimp and patiently tread water while waiting for the shrimp to clean its body of parasites. For the shrimp's part, it is usually quite diligent and will pick dead skin and necrotic material off the fish, keeping it disease free. This is a fascinating behavior to watch, not to mention practical in a reef tank where Ich outbreaks can threaten fish, but most Ich medications will kill off corals. The cleaner shrimps will be less shy if kept in 2-3 member groups; they will establish their own "cleaner station" on live rock and fish will know where to seek them when they require their services. Mine will even climb on my hands when I reach in to move corals around, cleaning off dead skin as though I were a fish! They are very sensitive to quickly changing water conditions, so keep water quality high. Healthy shrimp will molt on a regular basis, another fascinating thing to watch.