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Thread: Salt Water Test Trips vs Automatic Read Out

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    Salt Water Test Trips vs Automatic Read Out

    We just started the SWG yesterday and I was going through weekly tests:

    Strips (From TFP): 1300 ppm
    Hayward Readout: 2900 ppm

    I tend to believe the readout, but why are the strips so far off?

    Rest of Results below (prior to any adjustments):

    6/22/2013 8:30
    PH 8
    FC 8.5
    CC 0
    TC 8.5
    TA 90
    CH 80
    CYA 60
    SW 2900

    Notes: SWG Installed 6/21/13
    Add 32 oz. Muriatic acid
    Add 40 lbs. Salt
    Added 24 oz. of Stabilizer
    +/-16k gallon IG pebblesheen pool with SWG, spa and waterfall, Hayward 2HP 2-speed Tri-star, Hayward 1.5HP Tri-star, Hayward 5030 Cartridge filter, Hayward H400 Heater, Sharkvac Robotic Cleaner

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    Patrick_B's Avatar
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    Re: Salt Water Test Trips vs Automatic Read Out

    Assuming your strips are fresh and I'm guessing they are, I would trust them first. What was your salt before you added the 40lb?
    TFP Moderator
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    JasonLion's Avatar
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    Re: Salt Water Test Trips vs Automatic Read Out

    It is more likely that the SWG is correct, though it could go either way. The only common situations where the SWG are wrong (scaling and cell wearing out) all result in lower than actual readings.

    The test strips are usually quite good, but for some people they are way wildly wrong. They are also very sensitive to being exposed to moisture before being used.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
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    Re: Salt Water Test Trips vs Automatic Read Out

    The strips are just opened (received 2 weeks ago) and the SWG is brand new.

    I went with the SWG reading and added salt. Based upon the "taste test", it would appear the SWG was closer to being accurate.

    I will retest with the strips tomorrow and compare again.
    +/-16k gallon IG pebblesheen pool with SWG, spa and waterfall, Hayward 2HP 2-speed Tri-star, Hayward 1.5HP Tri-star, Hayward 5030 Cartridge filter, Hayward H400 Heater, Sharkvac Robotic Cleaner

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    Re: Salt Water Test Trips vs Automatic Read Out

    Quote Originally Posted by TAMC93
    The strips are just opened (received 2 weeks ago) and the SWG is brand new.

    I went with the SWG reading and added salt. Based upon the "taste test", it would appear the SWG was closer to being accurate.

    I will retest with the strips tomorrow and compare again.

    Todays results -
    Strips - 1,900
    Auto Reader - 3,500
    and still "tastes like salt"....

    Also - since I was circulating on a low flow setting the SWG spike the FC to 13.5. Guess it is working and I am reducing the percentage. Good to note in the future...
    +/-16k gallon IG pebblesheen pool with SWG, spa and waterfall, Hayward 2HP 2-speed Tri-star, Hayward 1.5HP Tri-star, Hayward 5030 Cartridge filter, Hayward H400 Heater, Sharkvac Robotic Cleaner

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    Patrick_B's Avatar
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    Re: Salt Water Test Trips vs Automatic Read Out

    Good for you. Whatever the reason, those are some lousy strips I guess.
    TFP Moderator
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    ABC's Of Pool Chemistry, Test Kits, SLAM Your Pool
    28K Gal IG FreeForm, CLI Quartz, Pentair 36"SF & VS Pump, Dolphin M5, Rheem

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