Acropora dying?

Hey guys - I have a 125 gal reef tank that has been running smoothly for a year or so now. Despite a skimmer issue recently (that Im talking about on another forum), things have been going well until a couple weeks ago.

I noticed my calcium levels were a touch low and so I dosed with the Reef fusion 1 and 2 and overshot. My alkalinity got up to about 14. All my other parameters have been stable, salinity, nitrates, nitrates at 0 etc.

I noticed the alk about 1-2 days after my dosing and I did a water change, but that day the acro started staying partially closed (about 1/2-1/3 polyps closed) and it has never recovered. Everything is ok now, but he is completely closed and appears to be starting to bleach out!!

My other sps are fine, i.e. birds nest, etc - as well as my mushrooms, softies, and xenia. Is there anything I can do besides watching this beautiful guy die?!?

Btw - the bleaching is coming from the base up, not tips down. Thanks!