Become a TFP Supporter Pool Math Forum Rules Pool School
Results 1 to 6 of 6

Thread: CYA and CH both decreased...

  1. Back To Top    #1

    CYA and CH both decreased...

    Hello,

    I've been back of the swing of things and performing complete pool chem tests with my TF-100 kit after a long winter of only testing chlorine and pH. When I first tested on March 6, here were my results:

    3-6-2014:

    FC 8.0
    CC 0.0
    TC 8.0
    pH 8.0
    CH 730
    CYA 90
    TA 110

    I've adjusted pH and chlorine as needed but I haven't tested cya or CH since. The other day I ran another full test and here's what I got:

    4-14-2014

    FC 7.0
    CC 0.0
    TC 7.0
    pH 7.4
    TA 100
    CH 500
    CYA 70

    What would cause big drops of CYA and CH over the course of a month? It has been raining and we've been swimming so there has been some splash out, but not enough for huge drops in those numbers. I'm kind if relieved because now I don't have to drain. I'm in hot Houston with full sun so CYA of 70 works well got me. I'm really concerned that I have a leak though. The pump looks fine and there is no water leaking at the pumps. Where else do I check for leaks? I do feel like I've needed to add extra water here and there but nothing substantial. Maybe and inch of water to keep it at appropriate levels.

    Should I just count my blessings or does this look like a problem? My pool warranty is up in June so Ud like to figure this out while the pool builder is still responsible. Has this ever happened to anyone before?
    17,000 inground gunite pool finished June 2013. Pentair variable speed something or another. Polaris cleaner, inline rainbow chlorinator. Using trichlor until CYA reaches 50-60.

  2. Back To Top    #2
    JasonLion's Avatar
    Join Date
    May 2007
    Location
    Silver Spring, MD
    Posts
    37,879

    Re: CYA and CH both decreased...

    Do you have an overflow drain? If so it would be fairly easy for there to have been more rain than you might have been aware of and enough water replacement to make a significant difference.
    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

  3. Back To Top    #3

    Re: CYA and CH both decreased...

    I do have an overflow drain and it's a possibility. According to the pool calc, I would need to drain 22% of my water to drop 20 points of CYA And that is 3,700 gallons. I can't imagine that much would drain away but I guess it's possible.

    When we built the pool, there was an area of gunite by the steps that always weeped water into the pool, but I doubt that water could drain out of that area after the luna quartz was sprayed on.
    17,000 inground gunite pool finished June 2013. Pentair variable speed something or another. Polaris cleaner, inline rainbow chlorinator. Using trichlor until CYA reaches 50-60.

  4. Back To Top    #4
    Mod Squad jblizzle's Avatar
    Join Date
    May 2010
    Location
    Tucson, AZ
    Posts
    37,389

    Re: CYA and CH both decreased...

    How much rain have you gotten? 22% would likely be around 10" (maybe less if your pool is deep)
    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!

  5. Back To Top    #5
    Isaac-1's Avatar
    Join Date
    May 2010
    Location
    SW Louisiana
    Posts
    6,711

    Re: CYA and CH both decreased...

    Judging by the rainfall here in SW Louisiana the last 6 weeks, I suspect houston is close to 10 inches in that time period, depending on exact location. Keep in mind this part of the gulf coast averages around 54-60 inches of rain per year.
    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~

  6. Back To Top    #6

    Re: CYA and CH both decreased...

    Thanks all! This is good news to me. I have been waiting to get paid so I can rent a pump and buy a backwash hose, but fortunately I don't need to anymore. My pool was built in June of last year so I haven't been through a rainy spring as a pool owner yet.
    17,000 inground gunite pool finished June 2013. Pentair variable speed something or another. Polaris cleaner, inline rainbow chlorinator. Using trichlor until CYA reaches 50-60.

Posting Permissions

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