Help and Advice

hi there guys and girls, been very very busy over the Christmas period, the tank is doing really well all parameters have settled in nicely, my aiptasia has gone thanks to the giant peppermint shrimp i bought named wrigglys who then subsequently died on me yesterday the reason i am posting is my once lovely hammer coral has been acting very odd during the daytime hours from 8am - 6pm roughly that i have my lights on there is hardly any polyp extension any more only tiny little white...