About 2 weeks ago i noticed 2 varieties of my palys were closed. After a few days i inspected the colonies and started treatment( coral rx/revive dips and after a week started iodine by seachem). I started to notice black spots/holes next 2 the "heads" of each polyp. The polyps were GOW and CB viper. After searching online came up with nothing. No other zoa/paly were efected. All colonies survived after switching systems and treatment . No other polyps left in original system have suffered. I've heard of zoa pox but not sure what the cause was. All polyps have healed since. Any ideas?