Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 8 of 8

Thread: What FC Loss To Expect

  1. Back To Top    #1

    What FC Loss To Expect

    Here are the details:
    South Arkansas
    97-100 Degrees
    Not much shade
    17,500 Gallon Fiberglass Inground Pool
    CYA of 40

    What would you expect the daily FC loss to be assuming no organics and no swimmers? Is losing 3ppm per day way too much or possible and even probable during times of intense heat?

    Thanks,
    Alan

  2. Back To Top    #2
    Mod Squad JohnT's Avatar
    Join Date
    Apr 2007
    Location
    SW Indiana
    Posts
    9,090

    Re: What FC Loss To Expect

    Sounds good to me. I'd have guessed 3-5ppm.
    TFP Moderator
    20K Gallon 20X36 Vinyl Inground
    Hayward S244T Sand Filter with 1HP Whisperflo Pump. Liquidator C-201 and Solar Heat

  3. Back To Top    #3
    Mod Squad woodyp's Avatar
    Join Date
    Apr 2010
    Location
    East Texas
    Posts
    9,004

    Re: What FC Loss To Expect

    FULL sun all day here too. Heat stroke days, high humidity, warm water---------I average 3.5 with CYA of 50. Target is 6 on the chlorine/cya chart and minimum for that is 4. I take mine to 8 to maintain minimum bottom number and a little cushion.
    16x32x52" Steel Cornelius Miramar AGP Vinyl liner 13,100 gal. Buried 2 ft.
    2 Speed Hayward Power-Flo Matrix 85 g.p.m. 22" 250lb. sand filter hard plumbed
    Pool Rover Jr., Pool Blaster Max, Diver Dave TF100 Test Kit/Speed Stir
    Margaritaville Frozen Concoction Maker, Liqour Chiller, & Drink Mixer & Party Tub----Collect 'um all!

  4. Back To Top    #4

    Join Date
    Aug 2007
    Location
    Jackson, NJ
    Posts
    61

    Re: What FC Loss To Expect

    I am in NJ and it has been hot and sunny most days. I average 3 ppm FC loss with normal bather load. That has been pretty consistent over a CYA range of 30 -50 ppm. Every pool is different and you just have to get comfortable with your own results. Luckily bleach is cheap!
    phil_d
    20,000 gal. vinyl liner pool
    Hayward Perflex EC-65 DE filter w/1.5 hp Hayward Super Pump
    Liquidator w/ 3/8" upgrade
    Aquabot Jr. pool cleaner

  5. Back To Top    #5

    Join Date
    Feb 2008
    Location
    Denton, TX
    Posts
    5,061

    Re: What FC Loss To Expect

    As hot as it has been, a 3 ppm loss over the course of a day sounds about right. Have you considered bumping your CYA up a little more? That might help some and is exactly what I have done this year.

  6. Back To Top    #6

    Join Date
    Jun 2008
    Location
    Lewisberry, PA
    Posts
    31

    Re: What FC Loss To Expect

    Quote Originally Posted by phildesantis
    That has been pretty consistent over a CYA range of 30 -50 ppm. Every pool is different and you just have to get comfortable with your own results. Luckily bleach is cheap!
    Amen to the every pool is different! South Central PA, one swimmer normally, 7 hrs full sun, 84 degree pool temp, lots of trees, oak, maple and pine, cya at 50, <0.5cc, overnight loss 0.5 to 1.5ppm. Can't seem to get mine below the 5-6ppm per day range even after shocking the heck out of it. Pool is crystal clear. I'm pretty convinced I've just got a steady influx of organics from the trees.

    So I'd say 3ppm is great!
    Roger

    14 x 28 Vinyl Inground, 13200 gal., Hayward EC-65 DE w/1hp Superpump

  7. Back To Top    #7

    Join Date
    Mar 2007
    Location
    San Rafael, CA USA
    Posts
    12,082

    Re: What FC Loss To Expect

    Quote Originally Posted by astrolite
    ... lots of trees, oak, maple and pine, cya at 50, <0.5cc, overnight loss 0.5 to 1.5ppm. ... I'm pretty convinced I've just got a steady influx of organics from the trees.
    With such a high overnight loss, I'd say your assessment is right on. You might try using skimmer socks that you clean regularly to try and capture and remove the debris from the pool more quickly and see if that helps. Of course, a pool cover is another option though you'd likely have a mess on top of the pool cover to remove every time you'd want to open/remove the cover.

    Note that larger debris, such as leaves, isn't going to have as much of an effect on chlorine demand as small particles such as pollen or seeds (the soft kind that float in the air).

    One more thing to note -- check your filter to make sure there isn't a lot of debris or possibly biofilm in it, though that's less likely with DE than with sand. You could also check behind light niches and under removable ladders just in case there may be yellow/mustard algae.
    16,000 gallon outdoor in-ground 16'x32' plaster pool; Pentair Intelliflo VF pump; Pentair IntelliTouch i9+3s control system; Jandy CL-340 square foot cartridge filter
    12 Fafco solar panels; Purex Triton PowerMax 250 natural gas heater (200,000 BTU/hr output); automatic electric pool safety cover; 4-wheel pressure-side "The Pool Cleaner"

  8. Back To Top    #8

    Join Date
    Jun 2008
    Location
    Lewisberry, PA
    Posts
    31

    Re: What FC Loss To Expect

    chem geek,

    I'm thinking more likely pollen than debris; I don't get that much large debris this time of year.

    The other possibility is red slime; I've been fighting that the last two years in a row. Pulled my ladder earlier this season and it was all over the bottom of it. Used some straight 6% bleach and a toothbrush, what a pain! Pulled off my skimmer plate and cleaned behind there. Don't have any lights or anything else. Threw all my pool toys in the pool while shocking. Bleached my swimming trunks. Concerned it could be growing in my return lines. Regularly dump chlorine in my skimmer to treat the filter and lines the best I can. Not sure what else to do along those lines. There is none visible but I don't suppose that necessarily means there's none there.

    At least the pool is crystal clear and from what I've read red slime is not dangerous to humans!

    alanrmeadows, sorry didn't mean to highjack your thread.
    Roger

    14 x 28 Vinyl Inground, 13200 gal., Hayward EC-65 DE w/1hp Superpump

Posting Permissions

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