Star Polyp??

[sandsifter]

just wanted to say hello first. History: been keeping saltwater aquarium for a coulple of years but just started a reef a couple of months ago. I have been having trouble with calcium and kh, got my water out wack so did a 50% water change last night. Today my green star polyp didn't open at all. Everything else seems o.k.(mushrooms,xenia,zoanthid,brains,trumpet) Just wondering if this is cause for concern?

 

[khilgers]

Mine have done the same thing for several days when I first introduced them to the tank. Don't worry about it they will come back out.