Verify salinity and tank temperature
They seem to fair well in lighting heavier in blue spectrum and iodine in their water. In case there is sand dust irritating them , give them gentle blasts with a turkey baster
This can be from to much light, I have seen zoas move down and to the sides of a plug when they are getting to much light. Try lower intensity , or move them down lower in tank.
Red Sea LED 90's, Salt 28.3, ORP 418, PH 8, TMP 77.9. Just did a 25% water change and salt seems a little low. Getting to the bottom of my mixing tank. Not all are spreading out, some seem to be thriving, but the one spreading out the most is up highest in the tank.