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Thread: Hardness question

  1. Back To Top    #1

    Join Date
    Apr 2016
    DFW North TX

    Question Hardness question

    So, I've been using the Pool Calculator for about a month with y'all's help.

    We've gotten a lot of rain this month so lots of fresh water.

    Got my water tested at Leslie's. The CH is 110.

    My PH is also 8. I already put in acid to fix the PH. Used Pool calculator for amount. Side note - I'm having a hard time keeping the ph down. Is that normal?

    Back to CH. The pool calculator recommended about 42 lbs of calcium chloride. I read on this site that PH can have an effect on hardness. Should I get the ph down and retest before adding calcium chloride? And any recommendations on where to get it?

    My pool is looking good with you help. Thanks!!
    30,000 gunite; Hayward 48 sq/ft DE filter;
    Pentair Kreepy Krauly Inground Pool Cleaner

  2. Back To Top    #2
    borjis's Avatar
    Join Date
    Aug 2014
    Pacific NW

    Re: Hardness question

    Pool store testing as you will see all over this forum is not trust worthy.

    First you should get a recommended test kit (Taylor K2006c or TF100) then post those results.
    They will be accurate.

    Some say ice melt works, but only if it's mostly calcium chloride...some are not..

    CH is the ONLY thing I buy at my local pool store.

    On the ph, first we need to know your Total Alkalinity level. It sounds like it might be high.
    The new thinking here is that lowering the TA then seeing what the ph does and for some
    they no longer need acid additions when the TA is at 50.

    When the TA is correct your ph should fluctuate a lot less unless your on new plaster, then
    that can take up to a year before it stabilizes ph levels.
    16x32 IG Vinyl, 13,000 Gals. Hayward S-244T sand filter, SP2810X15 pump
    (1.5 HP motor) Jandy Lite2 LJ250N gas heater. TF-100 Test Kit.

  3. Back To Top    #3
    Mod Squad
    Join Date
    Aug 2012
    DFW, TX

    Re: Hardness question

    No, PH has no impact on CH. I would raise it 250.

    Several things contribute to rising PH
    High TA
    Waterfalls, bubblers, etc
    Plaster that is less than a year old

    Order a TF100 from or a Taylor K-2006 from them or elsewhere.
    TFP Moderator
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    2012 build and pics, 20k gal gunite, black onyx pebblesheen, OK flagstone, IntellifoVS, cart filter w/Pleatco, IC40 SWG, Solartouch, 5 12'x4' solar panels, HP50HA heat pump, 8mil solar cover, borates, TF-100 test kit, SONOS, Doheny's Discovery Robot, hot tub on bleach

  4. Back To Top    #4
    frustratedpoolmom's Avatar
    Join Date
    May 2007
    SWSuburban Chicago, IL

    Re: Hardness question

    A low TA 50 or under can also cause rapid swings in PH.
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner

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