I agree with lion_crazz, "Get him some ghost shrimp, feed the ghost shrimp something nutritious, and then feed the ghost shrimp the lionfish. This is called gut-loading the ghost shrimp and the ghost shrimp can actually be good for him, unlike any kind of other live feeder you might find commonly sold."
If your lion is young it needs foods, feed some ghost shrimp gut loaded......
Pick up a feeder stick from your LFS, try Krill, Raw Shrimp, Crab, Frozen Sand Eels (thawed) and so on, your lion needs a variety of food, soaked in vitamins.
I would not recommend hand feeding any lion, get a feeder stick, feeding a staple diet of Freeze Dried will eventually catch up to your lion and health issue will follow.
also live food makes them way aggresive
Lions are predators, in general they are not aggressive, I have yet to see live food make a lion aggressive.
Kaye