i thought zoas were filter feeders? whenever any type of fish food lands on one of my zoas, they just close up...i do spot feed mine with microvert thoughand they have adjusted well, and ill be upgrading my lights from pc to t5 soon, i cant wait, im really excited... anyways, if a "zoa" is eating mysis, which is kinda big, maybe you should check to make sure you dont have a bad anemone colony like mojano, sometimes they look similar