When populating a new aquarium with the usual members of the cleanup crew (snails, hermits, etc.), people tend to overdo things initially. While there may be plenty of things to nibble on at the onset, a huge population of cleaners will quickly run out of food, eventually starving to death and leaving behind a huge pile of empty shells and exoskeletons. Like with any livestock stocking, add the cleaners to your tank slowly, over a long stretch of time. As the tank matures and you see that there is a need for more, add more until you reach a happy equilibrium. Keep in mind, however, that the cleanup crew can also affect how fish and other creatures behave as well. If your cleanup crew abolishes all forms of algae, then tangs and other grazers might not have enough around for the daily snacking that usually takes place. If you find that you have too many members of the groudscrew, you can move some of them into the sump or refugium, as there is usually plenty of stuff to eat in there. Or, you could place them in an another aquarium altogether, be it yours or someone else’s.