My friend called me up one time, thinking his tank was crashing. He was missing a goby, a dragonet, and a clown fish. In addition his dwarf fuzzy lion was laying on the bottem of this tank. After a few questions the one that gave the answer was, 'Wait, how big is your lion's stomach?'.
Each of those fish were in total length, the same size or not much smaller. They had been living together for at least a few months before he ate them. The really funny thing, is that he didn't eat the smaller clown.
Ocellaris and percula are definitly out. An XLG Tomato or Melanopus, a maroon, or maybe a blue stripe fiji.
Dwarf lions tend to have much bigger mouths than their size suggests. It's really about the diameter of their body. It's not uncommon for them to have half the fish out of their mouth while they're digisting the rest. I've seen them hold a fish for two days and then spit it out.