They can be very fickle,some of them grow all crazy and some not at all. I know that zoas taken from the sea take quite a while to begin growing in captivity where propagated will usually take right off. Ive noticed a lot more growth in mine since I really increased my flow,they simply love the flow. A lot of the time if they arent in good flow crud will collect around their bases,its a good idea to take a turkey baster and blow that stuff off every week or 2. Lighting is also important they seem to do best with moderate to high lighting,they will live down low and many will thrive there but it seems that most of them like a lot of light. Stable water parameters seem to help a lot too,your water doesnt have to be as perfect as with sps but its best that it remains stable. Good luck with your zoas,I notice you are from IN,I live in Indy and know several people/places to get good zoa frags cheap if you are near the area,pm me if you want and I can send you some links ect...