Knowing the origin of the zoa sometimes helps. Shallow zoas from around here in Florida, would do great in high light of course. Now Japanese deep waters are the opposite. They keep intense dark bold and beautiful colors, with low light. They fade and colors will blend together (instead of distinct separation lines) if not properly taken care of.
Frag a colony and place some in high direct light, and some in low or medium, preferably low. See who looks better to you. Then you will know for sure for that particular zoa.
Even if you take a high light zoa and place him in a lower light, you'll benefit from it. They will open up greater and evenly for you.
I feed my zoas cyclops (not often, once every 2 weeks), and I dose roties to the whole tank (1-2 times a week). The fish and cleanup crew get a homemade blend of almost everything you can think of. (shrimp, fish, scallops, mussels, octopus, oysters, clams, squid, nori, garlic, cyclops, brine, mysid, crab, vitamin supplement..) (every other day).
AND
Water changes, water changes, water changes... Zoas like "dirty water" not toxic water.