How do I slow fast rising pH

[FLHOKIE]

I have been struggling with keeping my pH from rising quickly. I can lower it with MA to 7.4 and then within a couple of days it is back to 8.0. I am told that new plaster pools have this issue.

This morning around 7 am the pH was at 7.4 and this evening at 7 pm it was already back up to 7.8.

Is there anyway to slow this down so I only have to add MA once per week? or even twice per week instead of daily?

The latest readings were:

FC= 4 CC = 0 pH=7.8 Acid Demand =1 TA=70 CH=390 CYA=60.

 

[jblizzle]

Not too much you can do.
All to these cause the pH to rise: aeration (waterfall / spa overflow), SWG, high TA

You could try keeping the TA a little lower, and maybe adding borates, but that is about all you can do.

 

[JasonLion]

It is completely normal for a new plaster pool to require acid additions daily for the first three to four weeks, and very little you can do about it. After that initial period the rate of PH increase will slow dramatically. PH increases will continue at the lower rate for about a year and then go away once the plaster finally finishes curing.