Got a pic? Or at least describe what's happening, I must have missed the other post. If some of them still look healthy I would frag and move to a different tank or at least farther away in good flow.
I'm having the same problem. Mine are stretching out and have white spots on them. The stalk becomes pinched and breaks off. I'm thinking it might be Zoa Pox.
look at you tank at night. do you see large pods over them? I had problems with pods swarming a few frags and eating them away. added a sixline wrasse and they stopped disappearing