It works great in the wild but whether it works in your tank is another question. There are alot of things that work in the wild but do not work here. Coral banded Shrimp for example are cleaners in the wild but 99.9% of the time they do not do that in captivity. The way you could try it is get the cleaner shrimp first, and then get the smallest grouper you can . Hopefully it will grow up side by side with the cleaner and get used to the cleaning activity and not see the shrimp as food.