Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 12 of 12

Thread: Intex gallon size discrepancy; today's water readings

  1. Back To Top    #1

    Join Date
    Jul 2015
    Location
    Corona, CA
    Posts
    16

    Intex gallon size discrepancy; today's water readings

    I was reading a thread from 2009 and didn't realize it so I posted a new thread to hopefully get some help today.

    I have the Intex AG 18' round x 48". The literature that came with the pool said 6400 gallons and the pool store said 7600 or so. I was thinking it was because I have the Ultra Frame and where the sides meet the bottom are not exactly square, but rounded. But now I wonder if I've been underchlorinating because I'm not using the correct amount of gallons in my calculations... Last night I added bleach using the Pool Math calculator to bring up my FC from 2 to 5. I added the amount per the calculator, but this morning my FC was only 2.6. My SWG was on yesterday too. Here are my measurements as of this morning:
    FC 2.6
    CC 0.6
    pH 7.6
    TA 52
    CH 170
    CYA 60

    My CYA has fallen from 70 to 60 in a few days. So, it seems I may need a teensy weensy bit more...? Any help is appreciated. Thanks in advance.
    18' x 48" Intex AG, 6700g
    1500gph Intex cartridge pump, SWG
    Installed June 2015 w/ city water (on restrictions)
    Taylor FAS-DPD 2006 kit

  2. Back To Top    #2
    Richard320's Avatar
    Join Date
    Jan 2010
    Location
    San Dimas, CA (LA County)
    Posts
    18,768

    Re: Intex gallon size discrepancy; today's water readings

    It's more likely you have an algae bloom starting and it just isn't showing up as murky water yet. I'd chlorinate heavily today and run an overnight loss test to ensure there's nothing growing in there. You can kill it off fast if you catch it early enough.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

  3. Back To Top    #3

    Join Date
    Jul 2015
    Location
    Corona, CA
    Posts
    16

    Re: Intex gallon size discrepancy; today's water readings

    NOOOOOO!!!! I HATE ALGAE.

    Ok, any advice on which gallon size I should refer to when measuring bleach to chlorinate heavily today?
    18' x 48" Intex AG, 6700g
    1500gph Intex cartridge pump, SWG
    Installed June 2015 w/ city water (on restrictions)
    Taylor FAS-DPD 2006 kit

  4. Back To Top    #4

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,077

    Re: Intex gallon size discrepancy; today's water readings

    6400 gallons is close enough. 7600 is incorrect.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  5. Back To Top    #5

    Join Date
    Jul 2015
    Location
    Corona, CA
    Posts
    16

    Re: Intex gallon size discrepancy; today's water readings

    Thank you duraleigh!
    18' x 48" Intex AG, 6700g
    1500gph Intex cartridge pump, SWG
    Installed June 2015 w/ city water (on restrictions)
    Taylor FAS-DPD 2006 kit

  6. Back To Top    #6

    TFP Guide

    Join Date
    Jun 2012
    Location
    western NY
    Posts
    1,557

    Re: Intex gallon size discrepancy; today's water readings

    My calculation at 48" depth of water is 7610.381 gallons. At 40" water depth it is 6341.983 gallons
    Unknown make 18' above ground (bought used in 1999) Sparco sand filter. Hayward 100,000 BTu heater. 2 speed pump

  7. Back To Top    #7


    TFP Guide

    domct203's Avatar
    Join Date
    Jun 2015
    Location
    CT
    Posts
    3,374

    Re: Intex gallon size discrepancy; today's water readings

    6700 gallons works perfect for me using Pool Math. I add 7-8 oz of 12.5% chlorine for every 1ppm I want to raise and that's what I get.

    30 minutes after you add chlorine (filter running) test and see if you have hit your target.

    If you want peace of mind for the algae do an OCLT (SWG off)

    Dom
    Dom - TFP Guide
    Intex 18' X 48" Ultra Frame AGP 6700 gallons | Two Intex CS8110 SWG's | Hayward Pro Series 21" Sandfilter | Hayward 1.5HP Power Flo Matrix pump | Hayward Thru-wall Skimmer | Wanda the Whale | 72 sq ft of Sungrabber Solar Panels with Hayward GLC-2P-A | Taylor K2006 Test Kit, Sample Sizer & Speed Stir | Click Here To Become a TFP Supporter!

  8. Back To Top    #8

    Join Date
    Jul 2015
    Location
    Corona, CA
    Posts
    16

    Re: Intex gallon size discrepancy; today's water readings

    Ah, thank you Dom!!! I have added 8.25% bleach TWICE at the recommended amounts per Pool Math and have not been able to get my FC up above 3. I had an inkling that I was using too few gallons in my calculations. This morning my readings are: FC 2.8, CC 0.4, pH 7.6, CYA 75. I've been trying to get up to 5ppm of FC and have not yet. I'll readjust and try again. Thanks again.
    18' x 48" Intex AG, 6700g
    1500gph Intex cartridge pump, SWG
    Installed June 2015 w/ city water (on restrictions)
    Taylor FAS-DPD 2006 kit

  9. Back To Top    #9
    Beens's Avatar
    Join Date
    Jul 2013
    Location
    Virginia Beach, Va
    Posts
    1,171

    Re: Intex gallon size discrepancy; today's water readings

    Are you sure your bleach is fresh?
    18' x 48" (42" water depth) Intex Metal Frame 6,700 Gallons
    Hayward Power-Flo LX 1.0 HP pump
    Hayward Pro Series S166T Sand Filter
    Original Intex Floating Skimmer

  10. Back To Top    #10

    Join Date
    Aug 2014
    Location
    Northern IL
    Posts
    4,615

    Re: Intex gallon size discrepancy; today's water readings

    Also, unless you need the accuracy for a tough OCLT, for FC/CC testing use the 10ml measure in your testing vial and multiply your drops by 0.5 instead of 0.2. Use the same powder and reagents.

    Check freshness of bleach and liquid chlorine (pool shock) by looking at the date code. 15212 is the 212th day of 2015.

  11. Back To Top    #11

    Join Date
    Jul 2015
    Location
    Corona, CA
    Posts
    16

    Re: Intex gallon size discrepancy; today's water readings

    I thought so. I bought it the day before I used it. I'll check the code as suggested by MarianParoo.

    - - - Updated - - -

    Thank you. I'll check the code! I just bought a 3 pack of Clorox from Sam's Club, but it could've sat in a warehouse somewhere, huh?
    18' x 48" Intex AG, 6700g
    1500gph Intex cartridge pump, SWG
    Installed June 2015 w/ city water (on restrictions)
    Taylor FAS-DPD 2006 kit

  12. Back To Top    #12

    Join Date
    Aug 2014
    Location
    Northern IL
    Posts
    4,615

    Re: Intex gallon size discrepancy; today's water readings

    Yea, you can never know where they stored it before they brought it inside. When I am buying boxed chlorine, I open the box and pull out a jug so I can read the date code. I have done this to multiple boxes at times. I just bought a 4-pack of 12.5% from Menard's for 3.99/gallon. 2 days old. The first box I opened was 5+ weeks old. Glad I checked another box!

Posting Permissions

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