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Thread: adding CYA?

  1. Back To Top    #1

    Join Date
    May 2007
    Location
    Huntsville, TX
    Posts
    15

    adding CYA?

    Tested CYA this morning & it's just below 30ppm - my test doesn't register any lower so I'm guessing it's somewhere in the 20's. The rest of my #'s are:

    FC - 1.0
    CC - 0
    pH - 7.7
    TA - 80
    CYA <30
    Temp 76

    What should I do next? I opened this year using BBB, but I still have plenty of chlor brite shock (sodium dichloro-s-triazinetrione dihydrate) & some trichlor tabs from last season that I could use if that will help add some CYA.

    If that's a good option, then how much do I add? Also, is there a trick to keeping CYA from dropping below 30?

    When I opened this year my CYA was close to 100, but thanks to a lot of rain this spring & only adding bleach instead of tabs, it's come down. Now I need to learn how to maintain it at the proper level.

    Thanks,
    Susie
    ~Susie
    27500 gal inground vinyl lined pool
    Pentair Clean & Clear Plus cartridge filter
    Pentair Whisper Flo 1HP pump

  2. Back To Top    #2
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879
    Are you confident about the CYA test? Dropping from 100 to below 30 would mean replacing at least two thirds of your water. That would be a lot of rain. If the water is cold, below 70, it is best to let it warm up at before testing CYA.

    Assuming all your numbers are right, now would be a great time to use up some trichlor pucks. Your PH is slightly high, your CYA is low, and you could use some more chlorine, the perfect combination for trichlor. You will need to keep an eye on your PH, eventually the thrichlor will bring it down and you will need to add some borax to bring it back up.

    I would aim for a FC level of at least 2, ideally 3 or 4. You might want to go to 5 when your CYA gets up to 30.
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  3. Back To Top    #3

    Join Date
    May 2007
    Location
    Huntsville, TX
    Posts
    15
    I am confident in the drop of the CYA level. I've been testing it regularly since the first of April & it has been slowly dropping over the last 2 months. I'm sure it's not all due to rain. Early on I drained some water - not to mention the Texas heat that comes & goes in the spring time.

    Now that I'm ready to add the trichlor, any advice on how much and how often? Is it OK to let it sit in the skimmer basket? I used to use a floater thingy but I got rid of it when I discovered BBB.
    ~Susie
    27500 gal inground vinyl lined pool
    Pentair Clean & Clear Plus cartridge filter
    Pentair Whisper Flo 1HP pump

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