Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 3 of 3

Thread: ok cya question along with an fc question

  1. Back To Top    #1

    Join Date
    May 2007
    Kannapolis, NC

    ok cya question along with an fc question

    Just checked my CYA and it if I am doing it correct is 50.
    So according to cya chart 20 is shock level. And according to how we all do this killing algea process we need to keep it there if possible, correct? And also when its so high 20 ish during the process of losing 4ppm and then adding back to 20. When the process is complete how will I know because we do tend to lose ppm during hot sunny days correct??? So will my nite test be the real determining factor.

    FC- 20
    CC- 0
    TC- 20
    PH- 7.4
    Alk- 80
    CYA- 50

    Water is clear but I had an overnite loss of 4ppm.

    So last question in this post I promise, When doing the FC test when it turns from red to clear I am done.

    Then I add the 5 drops and do I wait, because if I wait it will turn back red, just curious.
    My Pool:
    Foxx Pool Grecian style 19' X 39'
    27k, with a 300# sand filter

  2. Back To Top    #2

    Join Date
    Jan 2009
    Cupertino, CA

    Re: ok cya question along with an fc question

    You are done shocking when the overnight loss is 1ppm or less, CC is 0.5 or less, and the water looks clear.

    In the FC test, use the drops until the red/pink disappears. After 10-15 seconds and still colorless, use 5 drops of the R-0003 to test CC; if there is any it will turn pink immediately. Yes if you wait longer the pink will return, that's meaningless.
    BBB "Intermediate Swimmer"
    IG plaster pool 18.5K gal, Hayward Pro-Grid DE filter, 3/4 HP Hydramax II; Polaris 380, 3/4 HP booster
    AG spa 325 gal, probably Sundance of some kind
    Water testing instructions on one page

  3. Back To Top    #3
    JasonLion's Avatar
    Join Date
    May 2007
    Silver Spring, MD

    Re: ok cya question along with an fc question

    When you add the 5 drops of R-0003 to test for CC, it will turn pink right away if there is CC. It is normal for the solution to turn pink again if you leave it sitting for several minutes. That doesn't mean anything.

    It is the overnight test that tells you how you are doing at killing the algae. Since you lost 4 ppm of FC overnight, you still have more to go before you have killed it all.
    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

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts