[vertex]

I've got a beautiful open brain coral that I just love but the last week or so its really shrivelled up and gotten tight on its skeleton. I know they usually do this at times but it usually comes back the next day to its full puffed up glory.

I'm wondering if there is a problem or not or something they just do every now and then. (Its done it once before several months ago). I wouldn't want to loose it so I'm doing a bit of extra water changes. I still have very higher calcium at 450-500 and alk at 7-8 (which I'm trying to bring up slowly). Could this be affecting the brain? Anything else to do for it? I'll try feeding it but its not really opening its tenticles to collect food.