Ok after two 30 gallon water changes I have been able to drop my DKH to 15-16. Hopefully three water changes over the week will drop it to around 8-11dkh. Do yall think this high spike in alkalinity is the problem with the coral? my sps bleaching has gotten alot worse on a frag with 4 sticks about 2 are completely bleached, the other two the tips are bleached. any chance for recovery?

other params:
amm, nitrate, and nitrite -0
ph still 7.8
dkh - 15-16
calcium- 400
my calcium has drop alot since these water changes just added some liquid calcium to help with the drop.
Also anyone know how to increase PH without increasing ALK significantly?