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Thread: Is CC= 0.5 ok?

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    Is CC= 0.5 ok?

    I use a SWG and I have a AG pool 24 feet. For the last 3 weeks it has been raining a lot (I thought I should mention that).

    FC = 5
    CC = 0.5
    CYA = 60-65

    I just want to know if it is normal to have a CC = 0.5. After I tested the FC with TF-Kit, my water had a very little tint of Pink (very little), by adding one drop the water turned back totally clear (1 drop x 0.5 = 0.5 of CC).

    Is the CC = 0.5 normal or should it be 0 all the time?

    BIC
    Don
    SW Florida
    10,000 gal in ground concrete pool
    Pentair Cartridge filter
    Pentair Intelliflow pump
    Pentair SWG
    using BBB for pool chemistry/Lamotte ColorQ tester for daily testing

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    JasonLion's Avatar
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    Re: Is CC= 0.5 ok?

    CC of 0.5 is fine. The rain has probably brought some debris, which could cause the CC reading.

    [[Note: With the FAS-DPD test, one drop to clear CC is fine, so if you are testing so that one drop is 0.2, then 0.2 is fine but 0.4 is a problem.]]
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

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    Re: Is CC= 0.5 ok?

    Quote Originally Posted by JasonLion
    CC of 0.5 is fine. The rain has probably brought some debris, which could cause the CC reading.

    [[Note: With the FAS-DPD test, one drop to clear CC is fine, so if you are testing so that one drop is 0.2, then 0.2 is fine but 0.4 is a problem.]]
    With the TF-Kit: one drop is 0.5

    I don't get the idea. Is it the number of drops that counts or the value at the end? So if 0.5 is ok, that means that 0.2 x 2 drops = 0.4 cc should be fine too? But your are kind of saying it would not be ok?
    Don
    SW Florida
    10,000 gal in ground concrete pool
    Pentair Cartridge filter
    Pentair Intelliflow pump
    Pentair SWG
    using BBB for pool chemistry/Lamotte ColorQ tester for daily testing

  4. Back To Top    #4
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,887

    Re: Is CC= 0.5 ok?

    There are two ways to do the FAS-DPD test. The instructions with the TF-100 are for measuring by 0.5 per drop. But the same reagents can be used with different instructions to test for 0.2 per drop.

    The simple rule is that one drop to clear CC with a FAS-DPD test is just fine.

    The way things really work is more involved. It all hinges on how the test works. One drop to clear CC means that the actual CC level is above zero but not more than 0.2 or 0.5 (depending on how you do the test). In practice the CC level is almost always much closer to zero than it is to 0.2 or 0.5. We still call the level 0.2 or 0.5, but if you had a more precise test the true level would almost always be much lower.

    CC starts to cause problems when the true level is around 0.4. Using the test at 0.2 per drop it is easy to tell if you are below 0.4. Using the test at 0.5 per drop, if the test reads one drop you can't really be sure you are below 0.4, but the odds are very much in your favor that the level is actually below 0.4. In an outdoor pool, the odds that everything is fine are so good, that we don't bother to tell you to do the test over again with the other instructions to get a more precise level, it would just be a waste of time.
    19K gal, vinyl, 1/2 HP WhisperFlo pump, 200 sqft cartridge filter, AutoPilot Digital SWG, Dolphin Dynamic cleaning robot
    Creator of PoolMath and Pool Calculator. Other handy links: Support this site, TF Test Kits, Pool School

  5. Back To Top    #5

    Re: Is CC= 0.5 ok?

    Thanks Jason (once again ) for the info.

    BIC
    Don
    SW Florida
    10,000 gal in ground concrete pool
    Pentair Cartridge filter
    Pentair Intelliflow pump
    Pentair SWG
    using BBB for pool chemistry/Lamotte ColorQ tester for daily testing

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