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Thread: SLAMing for the first time

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    SLAMing for the first time

    After plugging in all my numbers in PoolMath, it's saying I need to add almost 5 jugs of bleach to bring my FC to 24 from 5. That seem like a WHOLE lot.
    Is that right?
    20,000 gal, in-ground, SWG, plaster, 2hp Hayward Ecostar variable, cartridge

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    Re: SLAMing for the first time

    Welcome to TFP Motheresa

    It is but not so much for bringing a pool up to SLAM level. What is the strength of the bleach you're going to be using ??
    Have you adjusted the pH ??
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    Re: SLAMing for the first time

    Keep in mind your pool is a pretty decent size. 5 gallons of 8.25% bleach adds 20ppm of FC to your pool. What is your SLAM number and how much FC do you have in the water before this addition?

    Once you start a SLAM the FC most likely won't be zero again, you'll be topping it off with fresh bleach frequently to bring it back up to that SLAM algae-killing level. THe more often you do that (even hourly at first) the faster the process will go.

    (*You can swim safely up to your SLAM level....as long as you can see the bottom)
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    Re: SLAMing for the first time

    Welcome to the forum. Looks like you did a lot of homework; good job!

    I assume you have a good reason to slam. I also assume you have a CYA of 60 and are using regular 8.25%, but anxious to see your complete test results.

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    Re: SLAMing for the first time

    My pool pump was taken out by a lightning strike (down for about 10 days) plus LOTS of rain = algae!
    CYA is 30, bleach is 8.25%

    - - - Updated - - -

    CYA is 30, SLAM number is 24??
    FC is 5.
    Good point about FC not going back down to original number after first SLAM, didn't think about that.
    Hourly is not too much?

    - - - Updated - - -

    8.25% bleach
    pH is 7.6
    20,000 gal, in-ground, SWG, plaster, 2hp Hayward Ecostar variable, cartridge

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    Re: SLAMing for the first time

    SLaM = Shock Level and Maintain. It's funny how many folks miss the Maintain part.

    - - - Updated - - -

    Hourly to start. As you notice that the FC is holding, you can stretch it out a little.
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    Re: SLAMing for the first time

    If your CYA is 30, your slam level to maintain is 12, not 24.

    If you didn't start the slam yet and your FC is still 5, lower your pH before you raise your FC to 12.

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    Re: SLAMing for the first time

    OH! I wished I would have read this first! I just put in 3 more jugs of bleach so it's going to be close to 24. Where did you find that information? I could only find the chart that starts at 60 (for SWG)
    20,000 gal, in-ground, SWG, plaster, 2hp Hayward Ecostar variable, cartridge

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    Re: SLAMing for the first time

    When you do a slam, you should just turn off your SWG and use liquid chlorine/bleach. Read the second to last paragraph here: Pool School - SLAM - Shock Level And Maintain

    I got that number from this chart: Pool School - Chlorine / CYA Chart

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    Re: SLAMing for the first time

    that's the chart I used, but it doesn't give SLAM FC for SWG with CYA less than 60
    also, from what I read, it seemed optional to shut off my SWG
    20,000 gal, in-ground, SWG, plaster, 2hp Hayward Ecostar variable, cartridge

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    Re: SLAMing for the first time

    Yes, it is optional... however, you should still use the non-SWG slam/shock level for your SLAM.

    You definitely have to turn it off for the OCLT at the end to test if you are done slamming.

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    Re: SLAMing for the first time

    What is the correct SLAM FC number since my CYA is between 30 and 40? That chlorine/cya chart doesn't list it for a SWG pool. Should I use the chart for non-SWG pools in this case?
    Also, when running my pump 24/7 while SLAMing, do I need to run it on the highest rpms (3250) or will a lower rpm work (like, 1725).
    20,000 gal, in-ground, SWG, plaster, 2hp Hayward Ecostar variable, cartridge

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    Re: SLAMing for the first time

    Go with 40 CYA if you are inbetween. That is a slam level of 16.

    Yes, use the non-SWG chart even if you decide to keep the SWG on.

    Lower rpm is fine.

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    Re: SLAMing for the first time

    Go with 40ppm CYA, so you want to try and MAINTAIN your FC at 16 as best you can. SWCG on or off at your discretion but off when doing the OCLT.

    If your pump ever dies on you again remember you can always make a run to the store and grab some bleach and use your brush to mix it around. Sump pump would be easier if you have one handy. It's one way to keep the green away until you're up and running again.
    '70s IG Vinyl 32K gal, Lazy L, Hayward SuperPump 1.5hp 120V, S240 Sand Filter W/DE
    Solar Blanket, Well Water, Borax Added, TF-100 tester. ? too cold
    1979, 275gal Conway Emerald Spa P-100-2, ES-2 Spa Pack, bromine floater, indoor
    TF-100, Best test kit - TFTestkits.net
    Please help keep the lights on, become a TFP Supporter!

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