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Thread: Went From Black to Bluish Grey but numbers off

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    Unhappy Went From Black to Bluish Grey but numbers off

    All,

    I opened my pool yesterday to black water, added 3 lbs of granular shock before reading how to turn your green swamp crystal clear.
    Pump has been running 22 hours.

    Today i have changed the DE twice and cleaned it out. But i decided i better do some test to see where i am at.
    Both kits have new chemicals last month form the manufacturer
    Quick test with K-1000
    Chlorine is 5
    PH is below the chart with yellow matching the chlorine test.

    TF-100 kit
    FC = 4.5
    CC=0
    TC=4.5 of course
    CYA is below 20 ( i never did get he black dot to disappear completely but it did get harder to see) did test 2 times
    TA= 10 (did test 3 times)

    Should i get the PH up using the calculator. or the CYA or both ?

    Help.
    27 ' AG Vinyl 18,400 gallons
    Pentair ECDE160 Easy Clean DE filter
    Optiflo 1 HP Pump
    Aquabot Pool Rover Sport (when it works) otherwise i have other names.
    TF-100 Kit

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    Richard320's Avatar
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    Re: Went From Black to Bluish Grey but numbers off

    Quote Originally Posted by johng1990 View Post
    All,

    I opened my pool yesterday to black water, added 3 lbs of granular shock before reading how to turn your green swamp crystal clear.
    Pump has been running 22 hours.

    Today i have changed the DE twice and cleaned it out. But i decided i better do some test to see where i am at.
    Both kits have new chemicals last month form the manufacturer
    Quick test with K-1000
    Chlorine is 5
    PH is below the chart with yellow matching the chlorine test.

    TF-100 kit
    FC = 4.5
    CC=0
    TC=4.5 of course
    CYA is below 20 ( i never did get he black dot to disappear completely but it did get harder to see) did test 2 times
    TA= 10 (did test 3 times)

    Should i get the PH up using the calculator. or the CYA or both ?

    Help.
    That low pH is going to be rough on any metal pool equipment in contact with it, but at least you don't have a plaster pool to dissolve.

    When pH is that low, adjustments can be pretty volatile without the dampening/buffering effect some TA adds.

    So...

    1) Raise TA to 50-60 ish. It doesn't need to be exact. If some even number if boxes gets you to 48, close enough. You can fine-tune later.
    2) After the baking soda has had time to dissolve and mix - half an hour is plenty if you also brush - recheck pH and TA and plug the readings into poolmath and target 7.2 pH. Add whichever you choose, borax or washing soda, to get to 7.2. If you have any leftover "pH up" or "Soda Ash" some pool store sold you, that's washing soda. Again give it time to mix. Recheck pH. It may still be below the scale. Just repeat the chemical addition until it's there.
    3) You're now ready to add some bleach. Shock level for 20 or less is 10 FC. Add that and brush again and recheck it in 10 minutes.
    4)If FC is greater than 5, and CC is less than 3, you don't have ammonia. You can add some CYA to get to 30 and proceed with the standard SLAMusing 12 FC as your target.
    5) If FC is less than 5 after 10 minutes or CC is greater than 3, post back and someone will type out the rest of it for you. I'm only adding this step because the pool was black and you have no CYA and we're seeing a lot of ammonia pools for some reason this season and since you added some CYA via the powdered shock and it isn't registering.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

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