There are numerous amount of shrimp species that are beneficial to the reef aquarium, however this guy is certainly one you don’t want to end up finding. The Mantis shrimp is a serious predator and will feast in the captive reef on small fish and inverts. The shrimp is an intelligent and well developed hunter, not easily caught.
Once you determine you have one in your reef tank, put together a game plan because you must remove this animal. Medium sized Mantis will hide amongst the rocks, and often make their home there. The larger specimens will acutely burrow in the ground. If possible remove the entire rock where the Mantis seems to be living, but make sure you wear gloves. If removing the rock is not a possibility you may find yourself needing to pick a fight with this guy and actually kill him inside of the aquarium yourself.
Another shrimp actually offered for sale at some LFS is the Saron shrimp, a fairly unique looking specimen but not entirely reef friendly. The Saron seems to keep to itself, but you’ll soon learn it’s a nocturnal predator. The shrimp will consume clams, corals, discosoma, zoanthus and sometimes even palythoa. keeping the Saron in the aquarium is not a risky as the Mantis, but if you chose to host this animal keep an watch full eye on your specimens and keep the Saron well fed. If you end up needing to remove the Saron practice the same methods as the Mantis by removing the entire rock. A few of the remaining shrimp to cover are the cleaner, peppermint, and banded coral some literature suggest these shrimp will eat coral when hungry enough, or at worst tear apart the tissue for ingested food.
The coral banded shrimp is said to catch small fish. I have seen the later, but personally have kept cleaner, and peppermint shrimp in tanks without a problem. In fact I recommend peppermint shrimp for the eradication of aiptasia. It is a common fact the shrimp will feed on parazoanthus after the elimination of the aiptasia and then move onto zoanthus. I personally would drop shrimp pellets in the tank for these guys to eat which seemed to keep them away from my zoos. Nothing is guaranteed however and you may get a particular specimen that has a preference to the zoanthus prior to other pests.