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Thread: Why is the Alkalinity so high?

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    Why is the Alkalinity so high?

    I just got my new Leslie's Chlorine FAS-DPD Service Test and so I am a beginner (even though I have lived with the pool for 10 yrs

    My TA is 300 but my pH is only 7.3
    I know my CYA is high, over 100

    pH is ALWAYS low - I am always adjusting up, have never ever added acid in 10 yrs.

    How can I lower TA when the pH is already on the low side? should I even worry about it? I am busy worrying about the CYA in an area where new water would be very expensive. I wish I had found this site sooner and understood chlorine chemistry

    TIA!
    very plain 1966 Rectangle, refiberglassed in distant past, 15K gall, Pentair 320 Cartridge filter
    Dolphin Diagnostics cleaner (the best!)

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    Re: Why is the Alkalinity so high?

    I think you need to aerate to bring up the PH and then add acid to lower it, and lower the TA.. Rinse and repeat until TA is in range.
    ~13000 inground plaster
    150sq Ft Cartridge Filter

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    Re: Why is the Alkalinity so high?

    Thanks for the reply - how do I aerate? just run the pump and filter more? I could take the cover off during the day if that would help
    very plain 1966 Rectangle, refiberglassed in distant past, 15K gall, Pentair 320 Cartridge filter
    Dolphin Diagnostics cleaner (the best!)

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    dmanb2b's Avatar
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    Re: Why is the Alkalinity so high?

    I would consider water replacement before worrying about your ta...is using a swg...you cya should be 70-80ppm or much less if just using bleach...then adjust your chemistry from there
    24'x52" AGP (13,500 Gallons), Intex SWG, (2)Solar Bear 4x20 panels, Hayward S220T Filter, 1/2hp Pentair Superflo

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    frustratedpoolmom's Avatar
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    Re: Why is the Alkalinity so high?

    First, retest the TA and wipe the tip of the dropper bottle in between drips with a damp cloth. JIC it's static that's causing the high TA reading.

    I can only assume years of puck/dichlor use is why your CYA is so high. It's alway why you are always adjusting ph/ta, because the pucks are acidic and lower both.

    You should do a partial drain to lower the CYA level first, before you tackle the TA issue. High TA is not necessarily critical at this point, unless one has an SWG. But high CYA is critical, because it can quickly lead to a green pool.

    Sorry, wish I had better news for you.
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
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    Re: Why is the Alkalinity so high?

    Yes I have been fighting the algae all season but its under control. I do a lot of sweeping and I clean the filters often so its acceptible. I confess that I thought it was a good thing those tabs dissolved so quick!

    Is the CYA is responsible for the low pH with a high TA??

    I just got the pool up to 85F (with solar) so I cannot replace the water now. I will have to invest in stocks ofthe Chlorox Corporation and Costco and muddle thru (like the last 9 yrs). I will leave the cover off more during the day, and as water evaporates, I will be able to replace it with fresh.

    Thanks for the replies!
    very plain 1966 Rectangle, refiberglassed in distant past, 15K gall, Pentair 320 Cartridge filter
    Dolphin Diagnostics cleaner (the best!)

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    Re: Why is the Alkalinity so high?

    Quote Originally Posted by Solvangswimmers
    Is the CYA is responsible for the low pH with a high TA??
    Adding CYA will tend to lower pH but does not change the TA. If you mean is that why the pH drops despite the high TA, it is certainly contributing if not the whole reason.
    Quote Originally Posted by Solvangswimmers
    I will leave the cover off more during the day, and as water evaporates, I will be able to replace it with fresh.
    The CYA won't evaporate, if that's what you wanted. You need to pump water out and replace with fresh, to lower the CYA.
    --paulr
    BBB "Intermediate Swimmer"
    IG plaster pool 18.5K gal, Hayward Pro-Grid DE filter, 3/4 HP Hydramax II; Polaris 380, 3/4 HP booster
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    frustratedpoolmom's Avatar
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    Re: Why is the Alkalinity so high?

    Exactly. As the water evaporates, the CYA level just becomes concentrated. Adding more water dilutes it back to it's prior level. YOu have to drain it out and then replace it with fresh. It's the only practical way.

    Solar will warm the new water up, I wouldn't let that stop you.

    If you do try to run with high CYA, maintaining your FC levels according to the CYA chart is essential, and you may want to consider maintenance dosing of Polyquat 60 algaecide, no substitutes, as a preventative. 50ppm Borates is another option.
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

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    Re: Why is the Alkalinity so high?

    Got it about the CYA becoming more concentrated - I could pump and replace after our 4th of July party. Is it OK to use the water to irrigate the lawn and other landscaping?

    How do I acheive 50 ppm Borates?

    Adding CYA will tend to lower pH but does not change the TA. If you mean is that why the pH drops despite the high TA, it is certainly contributing if not the whole reason


    what else do you think it could be? why is pH always around 7.2-.3 while Alkalinity is sky high?
    very plain 1966 Rectangle, refiberglassed in distant past, 15K gall, Pentair 320 Cartridge filter
    Dolphin Diagnostics cleaner (the best!)

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    Re: Why is the Alkalinity so high?

    Sorry, should be "adding trichlor will tend to lower the pH" as I doubt you are adding CYA directly.

    You haven't posted any description of your pool or gear, are you using trichlor tabs? That will put downward pressure on pH and increase your CYA.
    --paulr
    BBB "Intermediate Swimmer"
    IG plaster pool 18.5K gal, Hayward Pro-Grid DE filter, 3/4 HP Hydramax II; Polaris 380, 3/4 HP booster
    AG spa 325 gal, probably Sundance of some kind
    Water testing instructions on one page

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    frustratedpoolmom's Avatar
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    Re: Why is the Alkalinity so high?

    Quote Originally Posted by Solvangswimmers
    Got it about the CYA becoming more concentrated - I could pump and replace after our 4th of July party. Is it OK to use the water to irrigate the lawn and other landscaping?

    How do I acheive 50 ppm Borates?

    Adding CYA will tend to lower pH but does not change the TA. If you mean is that why the pH drops despite the high TA, it is certainly contributing if not the whole reason


    what else do you think it could be? why is pH always around 7.2-.3 while Alkalinity is sky high?
    I'm not sure about the landscaping watering, I don't want to give you bad info. When I drained my pool water 2 years ago due to high CYA, it did not kill my grass or the nearby tree....

    Here's the link for adding borates:
    http://www.troublefreepool.com/so-yo...how-t4921.html

    You're fill water could be high in TA.
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

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    Re: Why is the Alkalinity so high?

    Re draining, in some jurisdictions you're required to drain into the sewer, can't drain to the yard or street (storm drain). Those are the rules where I am, anyway.
    --paulr
    BBB "Intermediate Swimmer"
    IG plaster pool 18.5K gal, Hayward Pro-Grid DE filter, 3/4 HP Hydramax II; Polaris 380, 3/4 HP booster
    AG spa 325 gal, probably Sundance of some kind
    Water testing instructions on one page

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    Re: Why is the Alkalinity so high?

    Thanks I will call the city to double check about draining - I'm not sure they would know if I use a sump pump and attach it to a sprinkler. But I am DREADING it because its 15K gallons and water is expensive. Is there really no other way to decrease CYA? I dont even have an accurate reading because that black dot disappeared before I got up to 100 ppm.
    very plain 1966 Rectangle, refiberglassed in distant past, 15K gall, Pentair 320 Cartridge filter
    Dolphin Diagnostics cleaner (the best!)

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    Re: Why is the Alkalinity so high?

    There's no other sure-fire way to get rid of CYA.

    You can try diluting your pool water 50-50 with tap water and run the CYA test on that. If that shows under 100, double the result. Otherwise it's somewhere over 200.
    --paulr
    BBB "Intermediate Swimmer"
    IG plaster pool 18.5K gal, Hayward Pro-Grid DE filter, 3/4 HP Hydramax II; Polaris 380, 3/4 HP booster
    AG spa 325 gal, probably Sundance of some kind
    Water testing instructions on one page

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    frustratedpoolmom's Avatar
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    Re: Why is the Alkalinity so high?

    Can you put your pool specs in your signature? Go to User Control Panel, then Profile, the Edit Signature.

    Your CYA is probably much higher then.

    Is your pool 15,000 gallons? I'd drain down about 1/3 of the way, refill, recirculate and retest. Then see where you are at on the level.
    Helpful links: Pool School; CYA/Chlorine Chart
    24' round AG pool, 52" high, Raypak heater; Waterway 2 spd Pump;
    150 Sq ft. Clearwater Cartridge Filter; Former and DISSATISFIED "Pool Frog" owner
    http://www.PerfectlyClearPoolService.com

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    Re: Why is the Alkalinity so high?

    Testing to see if my signature stuck!
    very plain 1966 Rectangle, refiberglassed in distant past, 15K gall, Pentair 320 Cartridge filter
    Dolphin Diagnostics cleaner (the best!)

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    Butterfly's Avatar
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    Re: Why is the Alkalinity so high?

    Quote Originally Posted by Solvangswimmers
    Testing to see if my signature stuck!
    It stuck
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