Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 12 of 12

Thread: My CYA seems to be disappearing

  1. Back To Top    #1
    ajones02's Avatar
    Join Date
    Feb 2010
    Location
    Keller, Texas
    Posts
    118

    My CYA seems to be disappearing

    i need to chime in on this as well and looking for some assistance. on a previous post of mine, i mentioned that my CYA seems to be disappearing. i am adding about an inch of water every 3 days or so due to evaporation but with everything i've read, that should not be enough to cause the sudden drop in CYA. i read above that it's possible to be broken down into amonia and that a shock is necessary. just a few quick notes on my pool so far this summer. the lowest the FC has been was 3.5 and the highest CC reading I've had was 0.5 so I've never shocked my pool so to speak. the water has look good but at times not polished...Based on Jason's feedback above, is it advised that I go ahead and shock my pool to the proper levels to see if the CYA continues to disappear?

    Two weeks ago my CYA level was 80 and then i tested it last night and it was in the 55-60 range. same thing happened about a month or so ago as well. i also added 2 lbs of stabilizer this morning before coming to work.

    Thanks for any assistance.
    17,800 gallons, Pentair Clean and Clear 420 Cartridge Filter, Inground, Blue Granite Pebblesheen Interior, Pentair Intelliflo VS-3050 Pool and Spa pump, Pentair Whisperflo 2HP Water Feature pump, Pentair .75 HP Booster Pump for Pentair Legend pool cleaner, Pentair EasyTouch 8-function remote, Pentair IntelliChlor SWG.

  2. Back To Top    #2
    Melt In The Sun's Avatar
    Join Date
    Oct 2009
    Location
    Tucson, AZ
    Posts
    3,899

    Re: CYA level dropped off the charts.

    ajones, CYA -> ammonia can't happen in a sanitized pool. Evaporation and refill will have no effect on your CYA level, since the CYA doesn't evaporate with the water. I don't know what's happening...
    11,200 gal, Pebble-Tec; Tristar 2-speed 1hp - Swimclear 325 ft2 cart - SWG - A & A in-floor cleaner - Heat pump. For the poolside cooking, a Yoder Wichita and a Big Steel Keg!
    TF Test Kits -- PoolMath -- Pool School
    Make each day your masterpiece. - John Wooden

  3. Back To Top    #3
    ajones02's Avatar
    Join Date
    Feb 2010
    Location
    Keller, Texas
    Posts
    118

    Re: CYA level dropped off the charts.

    thanks melt in the sun for the quick response. just been a frustrating process. maybe i need to take a water sample to the pool store to verify the CYA as well.
    17,800 gallons, Pentair Clean and Clear 420 Cartridge Filter, Inground, Blue Granite Pebblesheen Interior, Pentair Intelliflo VS-3050 Pool and Spa pump, Pentair Whisperflo 2HP Water Feature pump, Pentair .75 HP Booster Pump for Pentair Legend pool cleaner, Pentair EasyTouch 8-function remote, Pentair IntelliChlor SWG.

  4. Back To Top    #4

    Join Date
    Dec 2009
    Location
    Central Massachusetts
    Posts
    2,690

    Re: CYA level dropped off the charts.

    ajones,

    Does your salt level go up at all when you lose the inch of water, or at least stay stable after you add water? Losing CYA like that and adding an inch of water every 3 days could be a leak. If the salt is dropping too, that could confirm. If the salt is stable, not sure what to make of it. Have you tested for ammonia?
    14,000 gallon IG, Vinyl. Hayward 3/4 hp superpump, Penatair IC40 SWCG, Pentair automation, Hayward sand filter, Aqua Comfort heat pump, Hayward 400k Lo-Nox LP heater.

  5. Back To Top    #5
    ajones02's Avatar
    Join Date
    Feb 2010
    Location
    Keller, Texas
    Posts
    118

    Re: CYA level dropped off the charts.

    actually FPM suggested a leak somewhere but the salt has remained stable at approx 3800 ppm for the past couple of months. i have not tested for ammonia yet. i was just actually reading some additional post and it appears that maybe my pool isn't quite as sanitary as i think it is and may need to test for ammonia. would the recommendation be test strips or take a sample to the pool store? if i do have ammonia, what is the process for removing that?
    17,800 gallons, Pentair Clean and Clear 420 Cartridge Filter, Inground, Blue Granite Pebblesheen Interior, Pentair Intelliflo VS-3050 Pool and Spa pump, Pentair Whisperflo 2HP Water Feature pump, Pentair .75 HP Booster Pump for Pentair Legend pool cleaner, Pentair EasyTouch 8-function remote, Pentair IntelliChlor SWG.

  6. Back To Top    #6

    Join Date
    Dec 2009
    Location
    Central Massachusetts
    Posts
    2,690

    Re: CYA level dropped off the charts.

    go to a pet store and pick up a kit. Not sure a pool store would test for it. they are pretty cheap. Chlorine and lots of it is the fix if you have it. My guess is you dont.
    14,000 gallon IG, Vinyl. Hayward 3/4 hp superpump, Penatair IC40 SWCG, Pentair automation, Hayward sand filter, Aqua Comfort heat pump, Hayward 400k Lo-Nox LP heater.

  7. Back To Top    #7
    ajones02's Avatar
    Join Date
    Feb 2010
    Location
    Keller, Texas
    Posts
    118

    Re: CYA level dropped off the charts.

    ok, i'll do that this afternoon and let everyone know the outcome.

    since this is my first inground pool, is an inch of water every 3 days or so a lot to replace? it's been around 100 degrees here now for about a week and a half
    17,800 gallons, Pentair Clean and Clear 420 Cartridge Filter, Inground, Blue Granite Pebblesheen Interior, Pentair Intelliflo VS-3050 Pool and Spa pump, Pentair Whisperflo 2HP Water Feature pump, Pentair .75 HP Booster Pump for Pentair Legend pool cleaner, Pentair EasyTouch 8-function remote, Pentair IntelliChlor SWG.

  8. Back To Top    #8
    ajones02's Avatar
    Join Date
    Feb 2010
    Location
    Keller, Texas
    Posts
    118

    Re: CYA level dropped off the charts.

    one other question in regards to a sanitized pool, i do have crepe myrtles somewhat close to the pool and have had a ton of the blooms fall into the pool over the past couple of weeks, would this possibly help the situation along?
    17,800 gallons, Pentair Clean and Clear 420 Cartridge Filter, Inground, Blue Granite Pebblesheen Interior, Pentair Intelliflo VS-3050 Pool and Spa pump, Pentair Whisperflo 2HP Water Feature pump, Pentair .75 HP Booster Pump for Pentair Legend pool cleaner, Pentair EasyTouch 8-function remote, Pentair IntelliChlor SWG.

  9. Back To Top    #9
    Melt In The Sun's Avatar
    Join Date
    Oct 2009
    Location
    Tucson, AZ
    Posts
    3,899

    Re: CYA level dropped off the charts.

    I don't think that's a lot; it sounds reasonable given the hot days. You can do a bucket test to be sure; fill a bucket partially with water and see you lose water from it at the same rate as from the pool. If you have a leak, the water level in your pool will fall faster than in the bucket.
    11,200 gal, Pebble-Tec; Tristar 2-speed 1hp - Swimclear 325 ft2 cart - SWG - A & A in-floor cleaner - Heat pump. For the poolside cooking, a Yoder Wichita and a Big Steel Keg!
    TF Test Kits -- PoolMath -- Pool School
    Make each day your masterpiece. - John Wooden

  10. Back To Top    #10
    ajones02's Avatar
    Join Date
    Feb 2010
    Location
    Keller, Texas
    Posts
    118

    Re: CYA level dropped off the charts.

    ah, i've read that on here before. i will try that as well!
    17,800 gallons, Pentair Clean and Clear 420 Cartridge Filter, Inground, Blue Granite Pebblesheen Interior, Pentair Intelliflo VS-3050 Pool and Spa pump, Pentair Whisperflo 2HP Water Feature pump, Pentair .75 HP Booster Pump for Pentair Legend pool cleaner, Pentair EasyTouch 8-function remote, Pentair IntelliChlor SWG.

  11. Back To Top    #11
    ajones02's Avatar
    Join Date
    Feb 2010
    Location
    Keller, Texas
    Posts
    118

    Re: CYA level dropped off the charts.

    first of all let me apologize to DLO for kidnapping his thread. if i need to start a different one i'd be happy to.
    Moved into it's own topic. JasonLion

    with that said, i stopped by and bought an amonia test at walmart and completed a full set of test and here are the results

    FC 5.0
    CC .5
    TC 5.5
    PH 7.2 was 8.2 on my original test but added acid to bring this down.
    TA 100 was 140 on my original test but dropped after bringing the PH down
    CH 300
    CYA 55 added 2 lbs yesterday to bring to 75
    SALT 3800 PPM
    WATER TEMP 90 (was 86 this morning)
    Ammonia best i can tell it was between .50 and 3.0 based on the colors. my best guess would be closer to 1.0 or 1.5 but there was noway to verify that.

    Thoughts?
    17,800 gallons, Pentair Clean and Clear 420 Cartridge Filter, Inground, Blue Granite Pebblesheen Interior, Pentair Intelliflo VS-3050 Pool and Spa pump, Pentair Whisperflo 2HP Water Feature pump, Pentair .75 HP Booster Pump for Pentair Legend pool cleaner, Pentair EasyTouch 8-function remote, Pentair IntelliChlor SWG.

  12. Back To Top    #12

    Join Date
    Mar 2007
    Location
    San Rafael, CA USA
    Posts
    12,082

    Re: My CYA seems to be disappearing

    When there is chlorine present in the water (i.e. a positive measurable FC reading), then there won't be any actual ammonia and the ammonia test kit will instead be measuring the amount of monochloramine in the water (chlorine and ammonia combine very quickly to form monochloramine). An ammonia test reading (with FC in the water) of 0.5 ppm would show up as 2.5 ppm CC since the units of measurement are different so something is very inconsistent here. It's certainly possible to have CC higher than predicted by the ammonia test (i.e. a CC higher than 5 times the ammonia test level), but the other way around doesn't make sense. If your CC were 5 ppm and your ammonia test around 1 ppm, then that would be consistent.

    I'd just chalk up the CYA drop to some sort of strange mystery and just adjust the chemicals and move on from here.
    16,000 gallon outdoor in-ground 16'x32' plaster pool; Pentair Intelliflo VF pump; Pentair IntelliTouch i9+3s control system; Jandy CL-340 square foot cartridge filter
    12 Fafco solar panels; Purex Triton PowerMax 250 natural gas heater (200,000 BTU/hr output); automatic electric pool safety cover; 4-wheel pressure-side "The Pool Cleaner"

Posting Permissions

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