Some zoas dont like being fragged.. For instance when i fragged 15 red hornets worth 30 per polyp 6 survived, other 9 shrunk, closed up and turned white and died within 2-3 days..
On the other hand i fragged probably 30 greenbay packers and not a single one perished using same method of fragging and not dipping. Thier definatly is a reason why some zoas are 100.00 + a polyp im sure some of the more rare ones might have higher mortality rates