Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 4 of 4

Thread: Inconsistency in readings

  1. Back To Top    #1

    Join Date
    Jun 2013
    Location
    Long Island, New York
    Posts
    1

    Inconsistency in readings

    Hi,

    I went to the pool store to get the water tested assuming that they will do a more accurate readings. Shocked to see the inconsistency of the results

    Yesterday readings:
    CYA 23
    TC 2.6
    FC 2.6
    PH 8.3
    TA 82
    Adj. TA 75
    CH 99
    Salt 3200
    TDS 4700
    Temp 70

    Today readings:
    CYA 80
    TC 3.1
    FC 2.7
    PH 8.1
    TA 81
    Adj. TA 57
    CH 80
    Salt 3200
    TDS 5000
    Temp 78

    - Yesterday I added 4 pounds of baking soda to raise the alkalinity and no other chemicals
    - It rained last night

    Questions:
    1. I cannot understand how CYA can jump from 23 to 80 in one day without adding any more
    2. Adjusted TA went down from 75 to 57 -- AFTER adding the baking soda!
    3. CH went down from 99 to 80 in one day!

    Are these readings possible or the pool store tests are completely inaccurate?
    Is it possible that I messed up taking the sample?

    Here is a history of the readings this season
    5/1 5/2 5/4 5/10 6/2 6/3
    CYA 0 0 51 41 23 80
    TC 0.8 0.4 0.3 4.7 2.6 3.1
    FC 0 0.4 0.3 3.7 2.6 2.7
    pH 7.7 7.2 6.8 7.1 8.3 8.1
    TA 71 70 44 73 82 81
    AdjTA71 70 27 61 75 57
    CH 107 98 115 163 99 80


    Any recommendations?
    (SWG vinyl pool, 35k gals, no heater)
    =================================================
    35,000 gals. vinyl pool, AutoPilot SWG, Pentair Variable Speed Pump, no heater
    Long Island, New York
    =================================================

  2. Back To Top    #2
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Inconsistency in readings

    Welcome to TFP!!!

    Quote Originally Posted by ndimtchev
    Any recommendations?
    As we tell just about every new member:
    1. Read Pool School to learn about the chemistry and methods we teach
    2. Order yourself one of the recommended test kits. Pool store testing is worth as much as you pay for it ... as you have discovered.
    Jason, TFP Moderator
    18k IG pebblesheen pool, Hayward ProLogic P4 w/ T-15 SWG, Pentair 1HP 2-speed Superflo, Hayward 6020 DE filter
    500 sqft Heliocol solar panels, ThePoolCleaner, TF-100 test kit w/ SpeedStir
    Pool School + Test Kit + PoolMath = A TROUBLE FREE POOL
    If you found TFP helpful and we saved you money ... Become a TFP Supporter!

  3. Back To Top    #3
    Mod Squad Bama Rambler's Avatar
    Join Date
    Jun 2009
    Location
    SouthWest Alabama
    Posts
    22,337

    Re: Inconsistency in readings

    That's a classic example of why we teach people to do their own testing with a good test kit.

    There's a few concerns that you need to know too. To us, the TA was fine, but the PS had you adjust it up which is going to cause you to have to fight the pH. And the pH was already high. That's what you needed to adjust.

    As JB said, spend some timereading Pool School and learning how to make your pool sparkle and your pool maintenance Trouble Free!
    Dave J. TFP Moderator
    24' x 52" Round AGP. 2hp/¼hp SPL Power-Flo 2-speed pump. 200sqft Waterway Cartridge Filter. 45MHP2(3GPD) Stenner Peristaltic Pump
    Pool School ----- Pool Math ----- TF-Test Kit

  4. Back To Top    #4
    Richard320's Avatar
    Join Date
    Jan 2010
    Location
    San Dimas, CA (LA County)
    Posts
    18,768

    Re: Inconsistency in readings

    Welcome!
    Quote Originally Posted by ndimtchev
    snip...

    Are these readings possible or the pool store tests are completely inaccurate?
    Is it possible that I messed up taking the sample?

    Here is a history of the readings this season
    5/1 5/2 5/4 5/10 6/2 6/3
    CYA 0 0 51 41 23 80
    TC 0.8 0.4 0.3 4.7 2.6 3.1
    FC 0 0.4 0.3 3.7 2.6 2.7
    pH 7.7 7.2 6.8 7.1 8.3 8.1
    TA 71 70 44 73 82 81
    AdjTA71 70 27 61 75 57
    CH 107 98 115 163 99 80


    Any recommendations?
    (SWG vinyl pool, 35k gals, no heater)
    It's pretty hard to mess up sticking your arm in a pool with a bottle in your hand. Which leaves us with option two...
    Recommendations, you say?

    Since you haven't admitted it but have likely been pool-stored, you're no stranger to spending money on your pool. This time, spend it on something that will actually do some good: http://tftestkits.net. I use and recommend the TF100 and a speedstir. I suggest you spring for the XL option now, saves shipping when you need refills later. You WILL use a lot of the FAS-DPD stuff when you first start. It's normal; we all obsessed over it when we got our new toy.
    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!

Posting Permissions

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