Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 13 of 13

Thread: CH jumped from 275 to 400-425?

  1. Back To Top    #1
    Ronald U.'s Avatar
    Join Date
    May 2015
    Location
    Pearland, Texas (near Houston)
    Posts
    83

    CH jumped from 275 to 400-425?

    I typically run CH 275 - 300. I didn't add any calcium intentionally (no Ca shock, Ca chloride). Today I was doing my weekly chemistries and find 400 and 425. What can cause such a jump? Thank you.
    Here are my other latest numbers:
    pH 7.7
    FC 6.0
    CC 0.5
    TA 80
    Salt 1800 ( about 10 days ago)
    CYA </= 40 (8 days ago; too cloudy just now to run test)
    Borate 40
    In-ground gunnite, 24k gal., Hayward DE filter, bleach, borate, Hayward Tiger Shark robotic cleaner, 75% full sun

  2. Back To Top    #2

    TFP Guide
    Mr Bruce's Avatar
    Join Date
    Mar 2014
    Location
    Greenville, SC
    Posts
    1,798

    Re: CH jumped from 275 to 400-425?

    What's your tap water? Have you had to replace water lost from evaporation or splash-out?
    32K gallon Plaster - 1hp Hayward 2 speed Super Pump - Hayward S200 Sand Filter - TF100XL
    Test Kits - Pool Math - Chlorine/CYA/Target/Slam Chart

  3. Back To Top    #3

    Join Date
    Jun 2011
    Location
    Long Beach, CA
    Posts
    2,670

    Re: CH jumped from 275 to 400-425?

    How much time has passed between the 300 to 400 readings?

    What does the fill water CH test at?

    The CH level in my pool increases about a 100 each summer due to evaporation and refill.
    16k gal plaster with raised spa, Jandy DEV60 filter, 2 HP 2-speed SHPF Jandy Stealth pump
    Hayward Aqua Rite T-15 SWCG, Jandy LXi 400k BTU NG heater, 350 sq.ft. of Sun Star solar panels, TF-100 Test Kit, Dolphin s300i Cleaner
    Test Kits . Pool Math . Chlorine/CYA Chart . The SLAM Process

  4. Back To Top    #4

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,084

    Re: CH jumped from 275 to 400-425?

    Since your weekly testing indicates a jump of 125 in one week, about the only logical thing that makes sense is a testing error.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  5. Back To Top    #5
    Ronald U.'s Avatar
    Join Date
    May 2015
    Location
    Pearland, Texas (near Houston)
    Posts
    83

    Re: CH jumped from 275 to 400-425?

    Fill water CH 200. / The only thing different in this week's testing is a new bottle of R-0012. Don't know how old this bottle is but I only started TFP and bought a TFT kit in May 2015.
    In-ground gunnite, 24k gal., Hayward DE filter, bleach, borate, Hayward Tiger Shark robotic cleaner, 75% full sun

  6. Back To Top    #6

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,084

    Re: CH jumped from 275 to 400-425?

    To my knowledge, "newness" has no affect on the CH test.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  7. Back To Top    #7
    Isaac-1's Avatar
    Join Date
    May 2010
    Location
    SW Louisiana
    Posts
    6,711

    Re: CH jumped from 275 to 400-425?

    Was your old bottle of CH reagent ever exposed to temperature extremes? You should store your test kit indoors in a cool dark place
    Indoor 20x40 35,000 gallon vinyl pool with 1.5 HP 2 speed Jandy FloPro pump, Hayward EC75 Perflex DE filter, 11 4x12 Techno-Solis solar panels w/ Aquasolar controller, Aquabot Turbo T Robot Cleaner. Also LMI metering chlorine dispenser pump and HotSpring Jetsetter
    I use and endorse TFtestKits TF-100 from http://tftestkits.net
    ~Remember TFP counts on your donations to keep this site ad free~

  8. Back To Top    #8
    Ronald U.'s Avatar
    Join Date
    May 2015
    Location
    Pearland, Texas (near Houston)
    Posts
    83

    Re: CH jumped from 275 to 400-425?

    Working kit is stored indoors but by a window. Spare chemicals indoors in a drawer.
    In-ground gunnite, 24k gal., Hayward DE filter, bleach, borate, Hayward Tiger Shark robotic cleaner, 75% full sun

  9. Back To Top    #9
    Ronald U.'s Avatar
    Join Date
    May 2015
    Location
    Pearland, Texas (near Houston)
    Posts
    83

    Re: CH jumped from 275 to 400-425?

    One week later my pool has increased CH again, to 425 - 450 (2 tests). I'm still scratching my head...
    In-ground gunnite, 24k gal., Hayward DE filter, bleach, borate, Hayward Tiger Shark robotic cleaner, 75% full sun

  10. Back To Top    #10

    Join Date
    Jun 2011
    Location
    Long Beach, CA
    Posts
    2,670

    Re: CH jumped from 275 to 400-425?

    How much fill water are you needing to add each week?

    Are you using a SpeedStir?

    A range of 400-425 and 425-450 is well within testing errors and shouldn't be cause for alarm. A CH of 450 is very manageable, hopefully some rains this winter will dilute it some.
    16k gal plaster with raised spa, Jandy DEV60 filter, 2 HP 2-speed SHPF Jandy Stealth pump
    Hayward Aqua Rite T-15 SWCG, Jandy LXi 400k BTU NG heater, 350 sq.ft. of Sun Star solar panels, TF-100 Test Kit, Dolphin s300i Cleaner
    Test Kits . Pool Math . Chlorine/CYA Chart . The SLAM Process

  11. Back To Top    #11
    Ronald U.'s Avatar
    Join Date
    May 2015
    Location
    Pearland, Texas (near Houston)
    Posts
    83

    Re: CH jumped from 275 to 400-425?

    No fill water was used in the week CH went up from 400 - 425 to 425 - 450. Just a bit of rain kept water levels up.
    In-ground gunnite, 24k gal., Hayward DE filter, bleach, borate, Hayward Tiger Shark robotic cleaner, 75% full sun

  12. Back To Top    #12

    In the Industry

    duraleigh's Avatar
    Join Date
    Apr 2007
    Location
    Sebring, Florida
    Posts
    30,084

    Re: CH jumped from 275 to 400-425?

    CH is probably the most stable of everything we test. It never leaves a pool and generally increases slowly, depending on amount of fill water.

    Since your testing seems dependable and repeatable, that can only mean CH is being introduced into your pool. What the source is I certainly can't tell.

    If you can't get it figured out soon, I would suggest you drain about a foot of water and replace it with your 200 CH fill water. That may be a permanent exercise unless you find the source.
    Dave S.
    42k vinyl and concrete pool, 1.5hp pump, 140gpm filter
    TFTestkits , PoolMath , Pool School

  13. Back To Top    #13
    Ronald U.'s Avatar
    Join Date
    May 2015
    Location
    Pearland, Texas (near Houston)
    Posts
    83

    Re: CH jumped from 275 to 400-425?

    I occasionally creep into the "potential" problem negative CSI (< -0.3 but > -0.6). I assumed this still means I am not leaching calcium from plaster walls. Extremely rare I go into < -0.6, and then for less than 24 hours. / I will ask my wife if she's applied anything in the surrounding vegetation. The case of the mysterious calcium.
    Last edited by Ronald U.; 09-20-2016 at 03:33 PM. Reason: mis-stated parameters
    In-ground gunnite, 24k gal., Hayward DE filter, bleach, borate, Hayward Tiger Shark robotic cleaner, 75% full sun

Posting Permissions

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