+ Reply to Thread
Results 1 to 9 of 9

Thread: Phosphates? High CYA!

Hybrid View

  1. #1
    chem geek is offline PF Supporter Whibble Konker chem geek 4 stars chem geek 4 stars chem geek 4 stars chem geek 4 stars
    Join Date
    Nov 2004
    Location
    California
    Age
    66
    Posts
    2,226

    Default Re: Phosphates? High CYA!

    Assuming the pool service was not using Trichlor pucks, they could visit once a week and add chlorine by having the CYA be high so the chlorine lasts longer and start the week with around 14 ppm or so and may end up at 4 ppm or so a week later. However, in your case, it sounds like it got out of hand and the chlorine wasn't lasting well enough so algae was able to grow when the FC got too low.
    15.5'x32' rectangle 16K gal IG concrete pool; 12.5% chlorinating liquid by hand; Jandy CL340 cartridge filter; Pentair Intelliflo VF pump; 8hrs; Taylor K-2006 and TFTestkits TF-100; utility water; summer: automatic; winter: automatic; ; PF:7.5

  2. #2
    onemsmom is offline PF Supporter Thread Analyst onemsmom 0
    Join Date
    Aug 2010
    Posts
    56

    Default Re: Phosphates? High CYA!

    After the pool company owner came out and saw that the CYA really WAS that high, he agreed to a partial drain & refill. After talking to him, it seems an employee probably shot the CYA really high & skipped a few visits. He had similar issues with other clients and employee has been fired. With all of that said, my pool is still green ( I was away for 2 weeks), the CYA is still too high (90ish) and the chlorine is at 1ppm. Ugh. So he is obviously not dealing with the problem properly and I will take my pool care back into my own hands. I STINK at being consistent, so this is hard for me, but I will do my best.

    I have forgotten how much bleach raises 1 ppm for my pool - could you please refresh my memory? I think it was 1/2 bottle = 1 ppm, but I'm not completely sure. I'm a 24' round - above ground - 13,000 gallons (I think).

    Here we go again.

    Thank you,

    Jennifer

  3. #3
    Join Date
    Jul 2010
    Location
    Largo, Florida
    Posts
    509

    Default Re: Phosphates? High CYA!

    In 13k gallons of water, 1 gallon of 6% bleach will give you 4.75ppm. So if your bottle = 1 gallon, 1/2 of that bottle gives you about 2.4ppm. At 90cya you need to be over 20ppm to shock.

    This is based on the best guess chart and your 90ppm cya. You need to KEEP it above 20ppm and keep testing for combined chlorine until your CC is 0, and you don't lose more than 1ppm FC between sundown one night and sunup the next morning.

    Once that happens you can let it drift down to 5-10ppm for regular operations. I keep my pool at that level of CYA (because my swcg recommends that level) so you can definitely run your pool at 90ppm cya.

    If you're not diligent enough to maintain things on a regular basis - and don't have a metal pool - then you might want to consider a salt water chlorine generator. You still have to stay on top of your pH (I usually dose with acid about once a week). A swcg won't help you clean up the mess though; you're going to have to do that the regular way.
    rectangle 11.5K gal IG concrete pool;; 125sf cartridge filter; 2hp 1 speed pump; K-2006, k-1766; PF:10

  4. #4
    onemsmom is offline PF Supporter Thread Analyst onemsmom 0
    Join Date
    Aug 2010
    Posts
    56

    Default Re: Phosphates? High CYA!

    Thank you so much!

  5. #5
    onemsmom is offline PF Supporter Thread Analyst onemsmom 0
    Join Date
    Aug 2010
    Posts
    56

    Default Re: Phosphates? High CYA!

    Question - would adding extra bleach buy me more time between checking/adding or make this process go more quickly or would it just waste bleach? Ex. if I'm supposed to keep the level above 20, would it speed things up to keep it above 30, etc.?

    Thanks,

    Jennifer

  6. #6
    chem geek is offline PF Supporter Whibble Konker chem geek 4 stars chem geek 4 stars chem geek 4 stars chem geek 4 stars
    Join Date
    Nov 2004
    Location
    California
    Age
    66
    Posts
    2,226

    Default Re: Phosphates? High CYA!

    For shocking, a higher FC level makes things go somewhat faster but the chlorine losses from sunlight are greater since they are based on the percentage of FC. However, speeding up the algae kill isn't the slowest part of the process. The slowest part is then removing the dead algae via filtration.

    As for regular maintenance, starting with a higher FC level will have it last longer, but because it drops as a percentage of FC you will be using more bleach. It's not "wasteful" so much as a trade-off between convenience of not adding chlorine as often vs. the extra cost associated with the larger amount of bleach that is needed.
    15.5'x32' rectangle 16K gal IG concrete pool; 12.5% chlorinating liquid by hand; Jandy CL340 cartridge filter; Pentair Intelliflo VF pump; 8hrs; Taylor K-2006 and TFTestkits TF-100; utility water; summer: automatic; winter: automatic; ; PF:7.5

+ Reply to Thread

Similar Threads

  1. High Phosphates
    By NelliNell in forum Pool Chemicals & Pool Water Problems
    Replies: 10
    Last Post: 07-22-2012, 06:03 PM
  2. Pool phosphates high
    By spawn1980 in forum Pool Chemicals & Pool Water Problems
    Replies: 3
    Last Post: 05-21-2012, 06:24 PM
  3. High Phosphates > 1,000 & High Nitrates 90ppm
    By applepar in forum Salt Generators (SWCG) & other Chlorine Feeders
    Replies: 21
    Last Post: 06-23-2011, 04:49 PM
  4. Phosphates?
    By Charlie in forum Testing and Adjusting Pool Water Chemistry
    Replies: 9
    Last Post: 11-15-2007, 02:53 PM

Bookmarks

Posting Permissions

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