High acid usage in a 2 year old gunite pool

BusterK

Member
May 2, 2021
5
Raleigh, NC
I have an indoor gunite pool installed 2 years ago. The pool is filled with well water (make up water is softened) with an ozone generator, mild chlorine treatment, and continuous automatic floor cleaning. I understand that new gunite pools consume more acid for up to a year as the concrete cures, but I've been consuming muriatic acid at about a half gallon a week since the pool was opened 2 years ago. The water is always in balance (LSI near 0) and crystal clear. TDS is around 2000 ppm. Could the ozone generator be oxidizing some of the dissolved salts causing the pH to rise? I've read that it's not necessary to drain the pool unless the TDS gets above 4000, but I wonder if I need to drain and refill with commercial water. Any suggestions?
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
14,013
Pleasanton, CA
Pool Size
20000
Surface
Plaster
Chlorine
Salt Water Generator
What is the current TA, CH & PH?

High TA can result in high PH.
 

BusterK

Member
May 2, 2021
5
Raleigh, NC
Have you tried to lower TA?

What is your fill water TA & PH?
My fill water TA is 150 and pH is 7.0. I've never let the TA get below 80. I just never thought of letting it drop of it's own accord to see where it would stabilize, but it's definitely worth a try. I'll let it go and see where it ends up in a few weeks. Thanks.
 

mas985

TFP Expert
LifeTime Supporter
May 3, 2007
14,013
Pleasanton, CA
Pool Size
20000
Surface
Plaster
Chlorine
Salt Water Generator
My fill water TA is 150 and pH is 7.0. I've never let the TA get below 80. I just never thought of letting it drop of it's own accord to see where it would stabilize, but it's definitely worth a try. I'll let it go and see where it ends up in a few weeks. Thanks.
With fill water that high, you may need to add an acid dosing system. It depends on how much of fill water you rely on and how often you will need to add acid.
 

BusterK

Member
May 2, 2021
5
Raleigh, NC
With fill water that high, you may need to add an acid dosing system. It depends on how much of fill water you rely on and how often you will need to add acid.
I have a Hayward system that monitors the pH and adds muriatic acid automatically. My concern is the amount of acid I'm using just doesn't seem right even with the 150 TA make up water. The pool is covered most of the time so evaporation and makeup water should be negligible.