Plaster manufacturer instructions said to keep the ph between 6.5 and 7. Im aiming somewhere in the middle. said to adjust alkalinity to 70ppm and check ph and if still above 7 to use acid to lower it. I will add stabilizer and check ph before adding acid. Hopefully I'm doing things right, thanks for the heads up. pool has 29.5k gallons, but i sure don't want to over treat.