Saltwater lobsters are nocturnal and feed at night. They live on the sandy bottoms of tanks or in the crevasses of rocks. Lobsters are relatively easy to keep and can be added to either fish-only or reef aquariums. Lobsters will eat anything they can catch so losses may occur. These animals are sensitive to changes in water conditions such as temperature, pH, and salinity. Medications containing copper should never be used in tanks with any hard-shelled crustaceans.