PH Nightmare, PLEASE HELP

[A Rai]

Hi guys, I need some advice for a customer of mine that comes in for a water test very regularly.

For the past few months I have been testing her water, and the PH is ALWAYS going up. Every 4 days she brings in a water sample to the store, and the PH tests at 7.8-8.0, and she is adding 1-2 tblsp of PH - into the spa. Her alkalinity level is always coming up at about 120-130, which lines up good as far as I'm concerned.

Her phosphates at about 500PPB, which she is putting some phosphate remover in to reduce in hopes it helps.

She is always filling her spa with a Carbon Pre-Filter to remove minerals, they use no bathing suits in the spa as well.

I am feeling very bad for her as this is a constant battle, and it is always going up to 7.8-8.0 every 4 days. She is on her fourth bottle of PH - in the past 3 months, and I was wondering if anyone here can offer some advice that I can pass onto her in hopes to help us win this ongoing battle?

Any advice is appreciated! If you need any more info I can provide that too if I have it!

[BullFrogSpasMN]

Alk. is too high, that needs to come down so the pH will 'level off'.....it's going to require multiple ounces of pH down, how many gallons in her spa?

[A Rai]

I've had her put A LOT of PH down into her spa, the chemical we sell reduces both PH and Alkalinity. My water testing system indicated that a alkalinity level of 100-150 is deemed acceptable?

Can you advise what level I should aim to get her alkalinity to in order to try to rectify this?

The spa is 1300L, or approx 340 gal.

[Tman122]

I would bring the ALK down to about 70-80. What are they using to sanitize?

[BullFrogSpasMN]

I would bring the ALK down to about 70-80. What are they using to sanitize?

I would recommend the same, somewhere in the 50-80 ppm range so the pH can stabilize, in a 350 gallon spa you'll need APPROX. 8 oz of granular pH/Alkalinity Reducer to lower Alkalinity by 50 ppm. Good Luck!

[A Rai]

Thanks guy, I should be seeing her today, I'll provide her with this and post an update in a few days with results!

[A.O.]

Agreed, I keep my TA at 50, her TA seems wild high.

 And Muriatic acid works better to control PH.

[The Wizard of Spas]

Pro tip on reducing pH and / or Alkalinity - when you add it do not turn the jets on.  You'll get greater reducing yields that way.  Leave the jets off for like a half hour, then turn them on for a cycle and test. 

When I used to have to reduce pH / Alk in swimming pools I found this to also be the case.  I'd put reducing agents in the deep end, diluted in a 5 gallon bucket, and run the pool for maybe 20 mints then shut off overnight.  Restarted the pumps in the morning and ran for a few hours and retested. 

Hope this helps.  Good luck moving forward.