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

Thread: Super high CYA--please confirm what I need to do next

  1. Back To Top    #1

    Join Date
    Jun 2016
    Location
    HUDSON, WI
    Posts
    5

    Exclamation Super high CYA--please confirm what I need to do next

    I just received my new TF-100 test kit and did the testing this morning. Here are the results:
    TC 5
    FC 4
    PH 6.8
    TA 170
    CH 400
    CYA 150

    I plugged these numbers into the pool calculator and was told to make the following adjustments:
    --add 57oz of washing soda OR 109oz of borax to adjust the PH
    --replace 73% of water with new water to adjust the CYA (a different amount of water replacement was suggested to adjust the TA--like 35%)??

    We "rebuilt" an old pool 2 years ago so all the water was replaced at that time. We have had a pool for 20 years and ALWAYS used dichlor. I don't know why we are having this problem now after all that time of using dichlor without issues. I have been using pretty much only liquid chlorine bleach for the past month or so with occasional pucks.(I was trying to increase the CYA level per my test strips!!)
    I had been testing multiple times per day since we opened the pool over a month ago, trying to figure out the problem with cloudy water, dead algae and no FC. I was using the Aquacheck test strips and I have been getting a TC of no more than 3 and a FC reading of 0-0.5ppm FC even the day after shocking the pool with up to 6 gallons of 10% bleach. Maybe the strips were old but they shouldn't be--can't decipher the date on them. Anyway, I won't be using those anymore. But I can't believe that the CYA readings on the test strips AND at the pool store were SO far off--pool store gave me a reading of 70ppm two different times.
    My question is how to get out of this mess. I'm having a confidence problem with trusting the TF-100 CYA results when everything else was telling me it was much lower.Please list the steps going forward--I'm guessing we need to drain about halfway down and then test again and adjust the chemicals. I HATE draining the pool. We live in Wisconsin and it was just getting warm!

    Please help--I need the experts to weigh in and rebuild my confidence in managing my pool!
    24,000 gallon IG pool
    Vinyl liner
    Sand filter (Triton--Meteor)
    1.5 HP pump
    Well water

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

    Re: Super high CYA--please confirm what I need to do next

    Welcome to TFP!!!

    And this is why we do not trust pool store testing OR test strips.

    You need to replace at least 50% of the water to lower the CYA. Leave at least 1 foot of water in the shallow end. If you have a very high ground water table, then you may not want to do all 50% at the same time and might need multiple smaller drains.

    After you fill up and circulate the water for at least an hour, then retest everything.
    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

    Join Date
    Jan 2014
    Location
    Buckeye AZ
    Posts
    807

    Re: Super high CYA--please confirm what I need to do next

    Did you get the 150 number by doing the CYA test diluted with tap water?
    10,500 gal IG, Topaz Pebble, auto-level
    Hayward DE filter, 2HP Ecostar VSP, ProLogic PS-4, GVA actuators
    Cal Pools Wave Force Plus (wall return jets plus 2 floor pop-ups), Venturi Skimmer
    Water sheer, 2 wok pots, bubbler stem on the baja step
    ColorLogic Mutlicolor LED lamp. Taylor 2006+speed stir

  4. Back To Top    #4

    Join Date
    Jun 2016
    Location
    HUDSON, WI
    Posts
    5

    Re: Super high CYA--please confirm what I need to do next

    Yes, I followed the directings for the "fading endpoint" and multiplied by 2.
    24,000 gallon IG pool
    Vinyl liner
    Sand filter (Triton--Meteor)
    1.5 HP pump
    Well water

  5. Back To Top    #5
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: Super high CYA--please confirm what I need to do next

    The CH has the fading endpoint ... not the CYA
    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!

  6. Back To Top    #6

    Join Date
    Jan 2014
    Location
    Buckeye AZ
    Posts
    807

    Re: Super high CYA--please confirm what I need to do next

    you can start your CH test with smaller samples and use a different PPM per drop calculation, like you would with a 10ml vs a 25 ml FC test. No multiplying at the end though.

    THe cya test, you fill the vial to the 7 oz mark with pool water, fill to the second 14 ml line with tap water, mix well, then pour out half to get the water line back to 7 ml.

    Then continue the test by adding the r-013 to get to 14 ml, mix for 30 seconds, then add to the tube. When you can no longer see the dot when you glance at it, you take your reading and multiply by 2.
    10,500 gal IG, Topaz Pebble, auto-level
    Hayward DE filter, 2HP Ecostar VSP, ProLogic PS-4, GVA actuators
    Cal Pools Wave Force Plus (wall return jets plus 2 floor pop-ups), Venturi Skimmer
    Water sheer, 2 wok pots, bubbler stem on the baja step
    ColorLogic Mutlicolor LED lamp. Taylor 2006+speed stir

  7. Back To Top    #7

    Join Date
    Jun 2016
    Location
    HUDSON, WI
    Posts
    5

    Re: Super high CYA--please confirm what I need to do next

    Oh, yes...thank you for correcting me! I did it both ways--first the usual way and then verified my results by diluting it with tap water and multiplying by 2.
    This pool chemistry is new for me--I appreciate learning from you all.
    24,000 gallon IG pool
    Vinyl liner
    Sand filter (Triton--Meteor)
    1.5 HP pump
    Well water

  8. Back To Top    #8
    Isaac-1's Avatar
    Join Date
    May 2010
    Location
    SW Louisiana
    Posts
    6,711

    Re: Super high CYA--please confirm what I need to do next

    One more thing, can you please add a state to your location, it helps us know your local climate and give better advice (The advice we might give someone in North Dakota with a 2 month swim season is different from someone in Florida with a 10 month swim season, etc.
    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~

Posting Permissions

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