Not every reef dwelling shrimp and snail are actually “reef safe”, though many of them are marketed that way. Two candidates that come to mind are the saron shrimp (Saron spp.) and bubblebee snail (Pusiostoma mendicaria). These two inverts have a conflicted standing in the aquarium trade. They are often sold as reef safe and sometimes hobbyists even have good experiences with them. Unfortunately, these two specifically have a taste for other critters in your aquarium. The saron shrimp has been known to eat other shrimp and even some soft corals. The bumblebee snail, on the other hand, is known to eat other snails. Of course, both of these predatory behaviors are usually exhibited when food is scarce. After all, it’s easier to be fed than to actually have to work for your food.