craig- well, if you want to put a fish in a tank with critters that might get eaten, you'd need to add the predator in last. It also helps to get it as small as possible. This lion wont get as big as a volitan, but still bigger than a dwarf. The size difference between my lion and shrimp was huge when i first put him in the tank so the lionfish will have "grown up" with the shrimp by the time he's big enough to pose a threat, they will have developed a semi- symbiotic/ commensal relationship. Plus he's been tank raised, most all fish that are tank raised are less aggressive twords things that would normally be food in the wild.