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Thread: [b]Calcium Hardness_When to drain and when not??[/b]

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    [b]Calcium Hardness_When to drain and when not??[/b]

    Calcium Hardness_When to drain and when not??

    I just got a calcium hardness test at my local Leslie pool store and its 575ppm

    They told me a month ago to drain my pool ( but not how much)

    We have just had a ton of rain over the last 4 weeks and i was going to drain my pool today but thought to get a new test.

    There test states ideal range of 200-400ppm and not to drain water from pool till it hits about 1,000ppm.

    Now my buddy has his local pool store computerized readout stating ideal is 175-225ppm

    Whats the correct amount?

    My pool is 28,000 gallon. How many gallons should i drain to get to the sesired level.
    Keeping in mind that our supply water is considered high in calcium.

  2. Back To Top    #2
    JasonLion's Avatar
    Join Date
    May 2007
    Silver Spring, MD
    There isn't a single simple answer to this question, it really depends on a large number of things. First you need to get a number for CH in your fill water. Then we need a complete set of test numbers for your pool water. The effects of CH in the water, and so the desired CH level, vary depending on the other numbers. How much water you might need to replace to get to some specific CH level depends on the CH level of your fill water.

    Appropriate CH levels vary from zero to over 1,000 depending on circumstances. For many people 200-400 is a good range, but with high CH levels in the fill water that is often impractical and other numbers get adjusted to compensate instead.
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    ktdave's Avatar
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    May 2007
    Katy, TX
    Also, is your pool vinyl-lined or plaster? That can influence your target CH level.
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