new gunite pool high pH

[sheddonaldson]

20k gallon gunite pool with diamond brite plaster. Plaster and fill was April 19th, only chlorine tablets were added until Salt and chlorinator on May 20th. After that it was handed over to me. I don't believe any acid was added during startup by contractor. When it was handed over to me by contractor, i was told to add 1/2 gal of acid per week and that for the first several months, ph will be high because of new startup. Pool has been crystal clear since day 3, and is still clear now, but pH is very high. 1/2 gal of acid per week only gets ph to 9.0. 1 gal of acid per week will get it around 8.0.

....all hayward equipment, chlorinator at 60% and all other chemistry levels are within range.


1.) Should i keep chasing pH, or just stick to 1/2 gal per week for the next few months?
2.) Should i try one big pH dump of 2 or so gallons and attempt to manage from there?
3.) How long will my ph want to continue to rise.

 

[Texas Splash]

Hello and welcome! It is true that new plaster (curing) will rise pH and can take several months to stabilize as noted on our Pool School - Start-up New Plaster page. But just adding an arbitrary number of acid (1/2 gal) isn't the way to control it. You definitely want to contain the rise and keep it below 7.8 to avoid the potential for calcium to leach out and become scale. To monitor pH and all your chemical levels we recommend either a TF-100 or Taylor K-2006C test kit (link below). With a new pool don't take any chances with anything less than the quality of one of those kits. I have the TF-100 and love it.

In fact, with the proper test kit, make sure to bump your numbers against all TFP recommended levels that can be found in my Vital Link below. By the way, don't forget to update you signature as well.

 

[ajw22]

When it was handed over to me by contractor, i was told to add 1/2 gal of acid per week and that for the first several months, ph will be high because of new startup.

The contractor did you no favors with that.

1.) Should i keep chasing pH, or just stick to 1/2 gal per week for the next few months?

As Pat said, get your PH down and keep it between 7.2 and 7.8. Add MA whenever it gets to 8.

2.) Should i try one big pH dump of 2 or so gallons and attempt to manage from there?

I don't know how you know the PH is over 9. Most simple PH tests only test up to 8.2.

Assume the PH is 8 and use PoolMath to calculate the MA to lower it to 7.4. Get your test kit and retest and repeat until your PH is in the 7's. Then monitor rPH regularly and you will get to know your pool and how long it takes for PH to get to 8.

3.) How long will my ph want to continue to rise.

Can be a few months or can be over a year. Every pool is different.