Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 7 of 7

Thread: What do I do about high FC?

  1. Back To Top    #1

    Join Date
    Apr 2009
    Location
    Lebanon, TN
    Posts
    19

    What do I do about high FC?

    I need some advice.
    PH 7.5
    FC 15.5
    CC .5
    TA 270
    CYA 100
    Salt 3700
    I had been running my SWG on 20% until yesterday, I turned it off around 5:00pm, these numbers are from about 5:00 today. What should I do to lower FC? Or will it go down on it's own? If so how long will it take?
    24' x 52" AG All Aluminum
    2hp 2speed 200sf Cartridge Filter
    Goldline AquaTrol
    4- 2x20 Sungrabber solar panels
    Goldline solar controler

  2. Back To Top    #2
    Casey's Avatar
    Join Date
    Apr 2007
    Location
    SW PA
    Posts
    9,929

    Re: What do I do about high FC?

    Hi and welcome to TFP!

    Your FC will drop on it's own. I wouldn't worry about it but moreso, I would suggest working on getting your TA down. It is very high and you can find info on it here at pool school.

    pool-school/lowering%20total%20alkalinity
    I'd bet you my bikini you'll never get TFP water from a pool store!

    24' Sharkline Venture De Filter

  3. Back To Top    #3
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,887

    Re: What do I do about high FC?

    The FC level will come down on it's own, though it will probably take a number of days to do so because your CYA level is so high. On the other hand, that isn't really all that high an FC level, given your very high CYA level. See the Chlorine/CYA Chart for appropriate FC levels for various CYA levels.

    One of the problems with a CYA of 100, is that is might actually be much higher. The most common CYA test will show levels higher than 100 as if they were 100. For that reason, and several others, I strongly recommend you lower your CYA level below 100.
    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

  4. Back To Top    #4

    Join Date
    Apr 2009
    Location
    Lebanon, TN
    Posts
    19

    Re: What do I do about high FC?

    So am I correct in that the only way to lower CYA is to lower pool and replace water? How is the best way to calculate how many inches to lower? To get where I need to be? ALso since my salt is a little high I can fix that at the same time.
    24' x 52" AG All Aluminum
    2hp 2speed 200sf Cartridge Filter
    Goldline AquaTrol
    4- 2x20 Sungrabber solar panels
    Goldline solar controler

  5. Back To Top    #5

    In the Industry
    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    28,415

    Re: What do I do about high FC?

    Probably the simplest way is to decide how many inches deep your pool averages.

    Say your pool averages about 60 inches deep. If you drained 12" and refilled, you would lower your CYA (and salt) by about 20%.

    It's not something you have to be really precise about and you may decide it's easier to do it in two or three partial drains rather than one big one. Simply retest after your first drain and refill and see how close you got to your target.
    Dave S. - Forum owner
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  6. Back To Top    #6

    Join Date
    Apr 2009
    Location
    Lebanon, TN
    Posts
    19

    Re: What do I do about high FC?

    Thanks for all the advice, on more question. If I decide to lower water level and then refill, will this also lower TA? If so it would seem that I could do all three of the things that need to be done with only two steps (lower and refill).
    24' x 52" AG All Aluminum
    2hp 2speed 200sf Cartridge Filter
    Goldline AquaTrol
    4- 2x20 Sungrabber solar panels
    Goldline solar controler

  7. Back To Top    #7
    gtm's Avatar
    Join Date
    Aug 2008
    Location
    St. Petersburg, Florida
    Posts
    201

    Re: What do I do about high FC?

    Whether the TA will lower with the drain and refill depends on the TA value of your fill water. If it's less than your current pool value, it will come down. It's probably best to just refill as much as you need to lower the CYA without worrying about the TA, and then test the TA again and see where you are. It might help, but first things first, meaning the CYA level.
    15,000 gal. IG fiberglass pool w/ 1 hp Hayward Max-Flo and 250 lb. Hayward sand filter
    Located in St. Petersburg, Florida, and enclosed in a birdcage

Posting Permissions

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