I have a 90gal tank and my ph can so from 7.98 to 8.13 I tried adding aqua vitro balance and it will rise then eventually sink back down if I add any type of coral should it be fine is my alkalinity, calcium and Kh is good?
As long as your alkalinity and calcium are okay I would not add anything to raise ph. Ph will fluctuate during nighttime and daytime. Alkalinity is what you have to keep stable 7-10 dkh Is okay. Don't worry to much about ph.