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Thread: test strip - show incomplete colour

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    test strip - show incomplete colour

    Hi, I am using quikchek test strips, but have had this issue with other test strips. What does it mean when the resultant colour is just around the border of the square instead of the whole square filled in? All the other test colours were complete (pH, total alkalinity etc) except for free chlorine and total chlorine - they only had the colour around the border of the square. thanks

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    Mod Squad Bama Rambler's Avatar
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    Re: test strip - show incomplete colour

    Welcome to TFP.
    If you'll do a little reading around here you'll find that strips (for everything except salt) are wildly inaccurate. Moisture incursion affects them in unpredictable ways and that may have happened to the ones you're using even if they're new.
    Dave J. TFP Moderator
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    Re: test strip - show incomplete colour

    Test Strips are wildly inaccurate and unreliable, best to read the pool school article on test kits pool-school/pool_test_kit_comparison for further information.

    A colour formed on a test strip which is lower or higher than that displayed is exactly that - lower or higher than the value displayed on the tin, just another reason to ditch strips.
    Stuart Murray
    Scotland UK
    UK NPPOC

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    UnderWaterVanya's Avatar
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    Re: test strip - show incomplete colour

    Quote Originally Posted by jacky
    Hi, I am using quikchek test strips, but have had this issue with other test strips. What does it mean when the resultant colour is just around the border of the square instead of the whole square filled in? All the other test colours were complete (pH, total alkalinity etc) except for free chlorine and total chlorine - they only had the colour around the border of the square. thanks
    No clue. As someone else mentioned the accuracy of the test strips is highly questionable - partially because the storage conditions prior to purchase as well as post purchase are a potential source of loss of accuracy. But more importantly, the way that the pool chemistry maintenance regime is done here requires higher degrees of precision than strips can provide. Even if they were 100% repeatable and accurate - they tend to have really broad ranges and don't provide enough accuracy for maintaining the pool using the BBB method.

    That said - I wish I could tell you what that means when the strip acts that way. Is there a manufacturer listed? Maybe you could contact them directly and find out.

    Just in case you want more of the details on accuracy concerns here's an older thread that discusses this topic: accuracy-of-test-strips-t29662.html
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    Re: test strip - show incomplete colour

    many thanks for the replys. Upon all your advice, I will ditch the strips.

    Cheers,

    Jacky

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