Lionfish are awesome, I want one as well but here are a few things that kept me from getting one, for the moment. There are different types of lionfish some can grow over 12" and some are considered dwarf that can reach 6". Keep in mind that they are predatory fish and will eat a tank mate if it can fit in its mouth. Most, if not all, are wild caught so they are used to eating live fish. Training them to eat prepared foods might be a challenge. As far as tank size, a minimum of 120g is required. Check out liveaquaria.com for more info.