I've had a small colony of zoas for several months and they appeared to be doing fine/spreading.  Recently, I've seen either swelling or bubbling of the polyps on the edge of the colony, and these polyps no longer open (or have a head).  Hopefully, the pictures will do a better job of explaining than I have...
Kevin
				
			Kevin
 
	 
 
		 
 
		 
 
		