I've had a pair of leaf fish several years. I have never been able to get them to take frozen, so be prepared to feed live at least weekly (2-3 times a week is better). Avoid keeping them with aggressively stinging/engulfing corals. They cannot compete with aggressively feeding fish and cannot escape from "pickers".
I have kept mine with seahorses, orchid dottyback, blennies, six line wrasse, wolf eel, waspfish.
They are very cool, just be sure you can feed them and supply mellow tankmates. I have kept them in low to moderate flow tanks.