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Thread: Shock questions

  1. Back To Top    #1

    Shock questions

    Had to partially drain SWG pool to remove and replace lights that had stripped screws. That is done!
    But the pool has sat still for a few days and now has algae - that I suspect got started when I let FC / TAC get to zero.

    I have to first replace the DE powder lost in the drain process.
    Then shock for the first time.

    I'm going to return the Algaecide I bought from Lowe's based on site recommendations.

    I estimate I need 6 40 lb bags of salt to get back to 3000. But I understand to shock I need bleach.

    Is there a calculation that tells me how much bleach to buy/ add?

    I see if CYA is at 60 I should shock to 24 ppm for SWG.
    Or do I just refer to the non SWG chart since my SWG won't create chlorine fast enough and isn't really a factor yet til I get it loaded with salt and generating? Will it help to add the salt and put on superchlorinate?

    Once I get to 24 or shock level, how long do I hold it there?
    At what ppm is it safe to swim? 2 - 4? And how long should I expect before we get there??

    May have to go to the neighborhood pool this weekend!!
    18K gallon Pebble Pool and spa/ Hayward H400IDL Heater/ Hayward Pro Grid 48 ft Vertical Grid DE Filter / Aquarite Chlorine Generator / 2 HP Hayward Northstar Pump /
    New pool owner since 2009

  2. Back To Top    #2
    Butterfly's Avatar
    Join Date
    May 2007
    South Carolina

    Re: Shock questions

    Yep, you chose the correct shock level.

    Please read How to Shock Your Pool and post back any quesitons you may have.

    You can use Jason's Pool Calculator to figure doses. Link in my sig and all over the forum
    TFP Moderator TF100 Test Kit TF100 TestKit YouTube Channel PoolMath
    You're done SLAMing when:
    1)You lose 1ppm or less FC overnight, & 2)You have .5ppm CC's or less, & 3)your water is clear.

    ~ One should not use a sledge hammer to swat a mosquito. ~

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