My Pool Requires Insane Amounts of Muriatic Acid

[IamMark]

Ever since we purchased our home 3 years ago, I've noticed that my pool requires an insane amount of 31.45% Muriatic Acid to keep the pH in line. I have to add 28oz of acid in my 14K gallon pool every other day to keep pH between 7.4 - 7.6. I know having a salt water generator causes pH to be higher than normal, but this just seems ridiculous. I was at my local pool store the other day buying my monthly case of 4 1-gallon jugs, and the pool owner there told me he would use that amount in 1 year.

Here are my numbers:

FC = 2.5
pH = 7.6
Alk = 75
CH = 475 (I know this is high, but I can't do anything about it right now - in California with water restrictions)
CA = 60
Salt = 3700 (recently discovered my SWG is highly inaccurate)
Temp = 83

Does anyone have any ideas what would cause such a heavy demand for Muriatic Acid and if there is anything that can be done?

Thanks!

 

[jblizzle]

Welcome to TFP!!!

You could raise the CYA and lower the SWG output which could slow the pH rise.
You could try to lower the TA a little more. (Is your fill water high pH and TA?)
You could try keeping the pH a little higher 7.6-7.8.
You could try to add borates.

 

[IamMark]

Thanks. My fill water's pH and TA is low. pH is 7.2 and I believe TA is around 50 or 60. During the summer time I pretty much have to run my SWG at 100% in order to to keep chlorine levels where they should be. What would be the advantage of keeping the pH a little higher?

Am I wrong in thinking this is a lot of muriatic acid to have to use? What kind of environmental factors contribute to high pH levels?

 

[jblizzle]

The pH does not rise as fast at higher levels. Having the SWG run that much is likely most of your pH problem.

Your cell is way undersized. We recommend sizing 1.5-3 times the size of your pool precisely to avoid having to run the pump and SWG all the time.

 

[Daltex]

Do you have any water features like a spa spill over? Aerating your water will increase the pH.

 

[ping]

The things I would do to help are:

Keep the pH 7.6-7.8 range.
Remove aeration from the pool, example; waterfalls, returns pointing up, spa spillover, etc...
Increase CYA to 80, that will help the SWG not have to work as much. Still might not do enough because the SWG is undersized.
Lower the TA to 60.
Replace the T-3 cell with a T-15 cell.

I agree that most of the pH rise is probably due to the SWG long run time. Research if you can replace the cell with a T-15 cell. There should be a calibration procedure that you can do that will adjust the electronic output of your supply. If there is an option for a T-15 cell then your unit can be used with a T-15 cell. Do a search if you do not know how to adjust the calibration. You will also save electrical money since you will only have to run a fraction of the time that the T-3 cell requires.

 

[Bart]

Add borates!

I have the same problem as you (SWG and raising pH). I did a borate treatment last year and it helped a lot. I still have to continuously add muriatic acid, but the borate treatment cut down my usage by at least half.