Alkalinity Burn or something else?

[NuraNori]

Picture from January with Full Color and Good growth


Taken Today with Browned out Color and tips burnt




Another Acro that is being affected




I want to make sure that it isn't something like AEFW that could be causing this.

My parameters are as follows 430 cal, 9 dkH, 1360MG, (salifert test) Nitrates, nitrites, ammonia and phosphates all undectable. (API test kits)
pH 7.9-8.2

I am right now adding 6g of reefbuilder alkalinity buffer in the am over the course of a 30 minutes and in the evening I dose 12 mL of calcium Kent's PartA. I know this isn't alot of additions but it seems to have stabled things out. I lost the color a little bit ago in alot of my corals because I added a few more corals (probably too many at a time) and my calc and alk levels got out of whack. I am now trying to stabalize everything and have been doing this addition for the past month.

Any info would be greatly appreciated.

Thanks in advance