How much T5? Duration of lighting?
How about your alk
did you mean your nitrAte was 0.1? Or you have detectable nitrIte? If you have detectable nitrIte that is a problem.
Are there any other corals in the tank? If so how are they doing? Especially any other zoas that are doing ok? Have you examined the zoas closely? I had a colony get zoa pox and it dang near wiped out all the zoas in my tank - probably 200 heads.