If trying to eliminate the colony as a whole I'd manually pull off everything immediately adjacent to the across then do you best everywhere else manually. Once done get some epoxy and put a sheet of epoxy where the colony was. Similar to how you can smother Aiptasia. Reef epoxy doesn't tend to stick so in a few weeks you can probably peel it off and spot treat any that pop back up.
Alternatively just move the acro sell the colony and rock, pop in a new rock and don't put zoa near it.