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

Thread: Different target levels

  1. Back To Top    #1

    Join Date
    Apr 2015
    Location
    Honolulu, HI
    Posts
    4

    Different target levels

    New member here. I've been maintaining my pool for several months with the help of this site. It's about a 12,500 gallon gunite pool with a salt water generator and bubble cover in sunny Honolulu, Hawaii:

    mypool.jpg

    The local pool professional I trust most recommended these levels:

    FC 3.0
    pH 7.4
    TA 120
    CH 150-200
    Salt 3400

    I've been shooting for these levels even though they differ somewhat from the TFP advice. My pH shoots up to 8.0 in a few days. I add about a gallon of muriatic acid per week. TA tends to fall to 90 if I don't add baking soda regularly. FC swings up and down, mostly depending on whether the cover is on or off (sunlight kills chlorine). I sometimes adjust the output of the SWG between 20% and 40%.

    Lately there have been white flakes in the end nearest the pump, paper thin, crumbly and not slimy. I suspect they are calcium scale from the SWG as described here. A test revealed that my CH has crept up to 350, so I have the triple-whammy: high pH, high TA, and high CH.

    Three questions:
    Is there a good explanation why the target levels would be different in Hawaii or for this specific pool?
    Should I be concerned about the rising pH and adding so much muriatic acid?
    Which reading(s) should I focus on lowering in order to prevent calcium scale?

  2. Back To Top    #2
    Mod Squad pooldv's Avatar
    Join Date
    Aug 2012
    Location
    DFW, TX
    Posts
    23,994

    Re: Different target levels

    Man! You Hawaiian pool people have some amazing pools and views!!!

    Welcome to TFP. Smart people will be along soon to help with how to stabilize your ph. I'm not there yet either.
    TFP Moderator
    If TFP helped you or saved you money - Become a TFP Supporter! <--Click here
    2012 build and pics, 20k gal gunite, black onyx pebblesheen, OK flagstone, IntellifoVS, cart filter w/Pleatco, IC40 SWG, Solartouch, 5 12'x4' solar panels, HP50HA heat pump, 8mil solar cover, borates, TF-100 test kit, SONOS, Doheny's Discovery Robot, hot tub on bleach

  3. Back To Top    #3
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Different target levels

    1. No. The local "professional's" recommendations are dangerous in that there is no mention of CYA which determines what FC level you need.

    2. No. Keep adding acid to maintain the pH in the 7s

    3. pH is the easiest the maintain, keeping it in line may slowly lower the TA which will also help. The CH will constantly climb due to evaporation unless you get enough rainfall to keep it lower.

    I am surprised you would ever need to raise the TA. With a SWG, it is better to have the TA lower to slow the pH rise.
    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!

  4. Back To Top    #4
    Divin Dave's Avatar
    Join Date
    Oct 2013
    Location
    Longview, Texas
    Posts
    4,926

    Re: Different target levels

    ^^^ What Jason says ^^^

    The pool guy is telling you wrong. If you want a troubleree pool, then follow the advice here and it will happen.
    If you want a headache, follow the pool guys advice.
    Divin Dave,
    IG Vinyl, 15' x 30', 3 1/2' - 6' deep, Oval, ~15K gal, Intelliclor IC40, Intelliflo VS pump, Clean and Clear 420 Filter, auto-fill-disabled, Retrofit LED Color Light, Dolphin Nautilus Robot, TF100 Test Kit, Taylor K1766 Salt Test Kit, Tftestkit Pressure Gauge.
    www.tftestkits.net Experience- it's what's learned just after you needed it most !!

  5. Back To Top    #5
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879

    Re: Different target levels

    The white flakes are from the SWG shedding calcium scaling.

    The PH is going up constantly primarily because your TA is way too high, and secondarily because you are trying to keep the PH too low.

    Not specifying or testing the CYA is very problematic.

    It would be good to test your fill water to see if the CH increase is coming from your fill water or not.

    The pool will be much simpler to maintain if you follow our guidelines. The SWG cell will also last longer.
    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

  6. Back To Top    #6

    Join Date
    Apr 2015
    Location
    Honolulu, HI
    Posts
    4

    Re: Different target levels

    Got it! Thanks for all of the quick advice.

    I've only tried to test the CYA one time and got no reading. This was with a Taylor K-2006 kit. The solution was not cloudy at all and the black dot at the bottom of the comparator tube remained clearly visible even when full. Either I performed the test incorrectly or the CYA was very low.

  7. Back To Top    #7
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879

    Re: Different target levels

    That means CYA was zero. When CYA is zero you lose chlorine to sunlight very very quickly. It also means you are at great risk of the SWG bringing the FC level up high enough to damage the equipment if the pool were to remain covered for a couple of days.
    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

Posting Permissions

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