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Thread: Hot Tub balance question - Jacuzzi J345

  1. Back To Top    #1

    Join Date
    Sep 2016

    Question Hot Tub balance question - Jacuzzi J345

    Question... Iíve been using the bleach dichlor method for the last 5 years - entire life of the tub. I read nitroís water balance many times and think Iíve been doing it right... or at least almost right.

    Jacuzzi J345 340 gallons

    I take my initial readings and plug them into the pool calculator and dial to zero or as close as possible.

    Where my my second guessing is coming in is it says to add dry acid until you get to 7.0 - 7.2 and then aerate again. But if I keep acid every time Iíll bottom out my TA trying to get my PH down.

    So I run all the jets, PH is usually 8 or even higher after aeration. When should you actually read the PH? Right after the aeration cycle or let it sit. If I check it after it aeration itíll be 8 if I check it with no aeration as itís been sitting itíll be 7.7.

    My my initial numbers were this: Fresh Fill - Ahh-Some purge 11/24/18

    TA 200
    CH 180
    PH 7.5
    CYA 0
    Borates 0

    My target TA was 80 if I follow the csi close to 0.

    TA 80
    CH 180
    PH 7.7 (non-aerated)
    CYA 7.8
    Borates 0

    It just feels like Iím missing something fundamental with the balancing. Iím usually around 65-70. But again I have never driven the TA down to 7.0 and then Aerate up to 8. It would seem that the water sits more non-aerated than aerated and would have a ph down in 7.0 to 7.2.

    Someone willing to pull my head out of the weeds on this one? Greatly appreciated!

  2. Back To Top    #2

    Join Date
    Oct 2017
    Roscoe, IL

    Re: Hot Tub balance question - Jacuzzi J345

    Adding acid to get your pH to 7 and aerating is how you lower your TA from a really high amount (200 for you, 250 for me) to get it close to 50. Once your TA is getting close to 50, stop targeting a pH of 7. Start targeting a pH of ~7.4-7.5, and once your pH remains stable somewhere around 7.4-7.8 after aeration, you're done. This varies based on water supply but typically happens around a TA of 50.

    Another thing to note is don't worry if you CSI is negative. Negative CSI has zero concern for a fiberglass or vinyl spa or pool, it's only a concern with stone/gunite spas or pools. Negative CSI won't corrode metals, it just dissolves calcium out of stone/gunite. pH is all that really matters for metal corrosion, if it's above 7 it should be fine (and 7 is lower than you want anyway). That's where the 7 comes from when adding acid to lower TA. It's just the lowest you want to bring the pH to avoid damage to heaters/etc.

    Hope this helps!
    Hot tub: Indoor Intex 28409E "Six Person" inflatable. 290 gallons. Taylor K-2006 test kit with Taylor 9265 Speedstir and TFT CYA test. Using dichlor/bleach/borax/muriatic acid.

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