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Thread: Scared of Trichlor but need CYA

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    Scared of Trichlor but need CYA

    I drained and refilled to get rid of high CYA and solve algae problems. I understand much more now thanks to the School and Forum

    I need to add some CYA to protect my FC, and I have a whole bucket of Trichlor pucks. But I am scared that I will end up with low pH problems.

    Is it EVER ok to trust Trichlor? should I use Dichlor (and add it slowly, test for CYA frequently) or buy plain CYA?

    What do I do with a nearly full bucket of Trichlor pucks!
    very plain 1966 Rectangle, refiberglassed in distant past, 15K gall, Pentair 320 Cartridge filter
    Dolphin Diagnostics cleaner (the best!)

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    Re: Scared of Trichlor but need CYA

    What's your current CYA? Just to be sure you need some. If you did a total drain and refill, your CYA is zero and the pucks won't add CYA fast enough to be helpful; you'll want some pure CYA. If you already have dichlor sitting around then you might as well use it up, but I wouldn't go buy dichlor to get CYA, I'd just get the CYA.

    You aren't the only one with a bucketful of pucks... I use mine when I go on vacation, 2-3 pucks don't add that much CYA, it's the cumulative use over many months that get you into real trouble.

    Pucks are supposed to lower pH but you know... it depends on the pool. Mine has a distinct upwards trend, and with pucks in there it just slows or possibly even stops the rise. If your pH is normally stable then it might be an issue.
    --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: Scared of Trichlor but need CYA

    Thanks Paul

    Yes a total drain because the Pool Calculator recommended 80% and at that point, what's another 20%....
    and CYA is zero (or at least well below the detectable 10 ppm) according to the Black Dot Test.

    I have always had problems with low pH and I think it was because of the Trichlor, which I always used, but who knows

    I have a bunch of 1 lb bags of Dichlor. Will the CYA be available immediately or does it take time to dissolve when you use Dichlor?

    I am so paranoid about CYA that I bought a whole gallon of reagent and have been testing it daily.
    very plain 1966 Rectangle, refiberglassed in distant past, 15K gall, Pentair 320 Cartridge filter
    Dolphin Diagnostics cleaner (the best!)

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    Cherie's Avatar
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    Re: Scared of Trichlor but need CYA

    After the winter and some really torrential downpours, our CYA dropped to about 15. So I've been taking advantage of it this summer by using up our tabs from our pool install last year. Of course, our pH and TA were already very stable. I keep the TA at 60 and pH at 7.3 - 7.5. We haven't been able to swim much this year though, since we're installing the deck around our pool right now. (And the City just threw a couple of monkey wrenches into our plans as of yesterday)

    So I've just been keeping 3 of the 3" tabs in the floater, tied to remain in the middle of the pool and it lasts for about 10 days. I just check my FC/CC and pH each evening or every-other-evening, and check the TA every couple of weeks. I knew they were used up tonight because my FC was at 1.5, where it's almost always at 2.0 - 2.5 by the evening.

    This may all change when we get to start swimming again! But for now, the tabs sure have come in handy. And yes, it will take a good long while for the tabs to get the CYA up to the recommended level of 30-50. Meantime, I'm in no hurry, since all I'm doing these days is checking my levels and adding 3 more tabs every 10-14 days.
    32x16 buried Doughboy, 4' shallow - 7' deep
    Pentair Dynamo 1 hp, 2-speed - Pentair 150# SD40 w/zeolite (75#)
    One skimmer/two returns/Aquabot Turbo T2

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    Re: Scared of Trichlor but need CYA

    Cherie - Trichlor also affects Alkalinity? Great, now something NEW to worry about. I will have to fish that tab floater out of the pool tonight or I will have nightmares.

    I hope your deck plans get approved soon!

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

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    Re: Scared of Trichlor but need CYA

    Quote Originally Posted by Solvangswimmers
    I have always had problems with low pH and I think it was because of the Trichlor, which I always used, but who knows
    Trichlor is acidic, that is at least a contributing factor. Dichlor is also net acidic, so you'll continue to need to watch the pH until you stop using it. Bleach (and cal-hypo) are pH neutral, so after you switch to bleach, your pH behavior will likely change.
    Quote Originally Posted by Solvangswimmers
    I have a bunch of 1 lb bags of Dichlor. Will the CYA be available immediately or does it take time to dissolve when you use Dichlor?
    Dichlor dissolves pretty easily and I believe the CYA is pretty much there right away. You should add the dichlor according to how much chlorine you want. Then for every 10ppm FC from dichlor, you will also get 9ppm CYA. (So if you add enough dichlor to raise FC by 5, twice, then you've added 10ppm cumulative FC and therefore 9ppm CYA.)
    Quote Originally Posted by Solvangswimmers
    I am so paranoid about CYA that I bought a whole gallon of reagent and have been testing it daily.
    Okay, time for a couple of deep breaths! CYA does not change, unless you put some in, or take water out. It's not like pH or FC which can change without you doing anything.
    --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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    Cherie's Avatar
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    Re: Scared of Trichlor but need CYA

    Oh gosh, Heather! NOW I really feel bad I don't recall what your TA was (did you say?). I just wanted to mention how easy I'm finding it this summer to take advantage of having a really low CYA and just letting the tabs do all the work for me..until I hit the magic number! But then, I keep my CYA at around 20-25 anyway because our pool simply seems to hold FC very well, whether we keep it covered or not. With our pool, even before the downpour this spring that finished off our CYA, we were using very small amounts of bleach each evening - which I was very pleased with.

    You'll just need to take the time to get to know your water. Last summer, when we had our pool put in, I went through a TON of reagents getting to know our water. I'm sure our neighbors are convinced I'm a real fruitcake, because I tested our water several times daily so I'd know what to expect with normal circumstances! But I feel very comfortable with being fully in charge of our pool now...although the pocketbook hurt a bit last year -- especially BEFORE we found this site!
    32x16 buried Doughboy, 4' shallow - 7' deep
    Pentair Dynamo 1 hp, 2-speed - Pentair 150# SD40 w/zeolite (75#)
    One skimmer/two returns/Aquabot Turbo T2

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    Cherie's Avatar
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    Re: Scared of Trichlor but need CYA

    And thanks for the well wishes on our deck. I fear they have it out for us now though. If you can believe this, we (meaning DH and MYSELF) put in the Kentucky Rail fence around our back yard (we live on an acre lot) AFTER obtaining the permit - got it done, got it signed off. We also got our pool permit, got it done, got it signed off (which the city now says we DID NOT get signed off and I now have no paperwork to prove the sign-off - I only have the proof of permit). So NOW, after dropping off our paperwork nearly two weeks ago for our deck permit and being told they'd take care of everything and call us to come pick it up, they're giving us a hassle over our fence (saying it's not legal -- FOUR YEARS after we installed it) and saying our pool does not have final approval. AND they now say they can't find any paperwork that I "claim" to have dropped off two weeks ago. ggrrrrrrrrrrr

    But hey, our deck is looking great and I can't wait to post pictures of deck build - again being done by just DH and myself...in the Texas heat ... unable to jump in the pool and cool off ...

    OK, I'm done threadjacking and now return to the regularly scheduled conversation for this thread!!
    32x16 buried Doughboy, 4' shallow - 7' deep
    Pentair Dynamo 1 hp, 2-speed - Pentair 150# SD40 w/zeolite (75#)
    One skimmer/two returns/Aquabot Turbo T2

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    Re: Scared of Trichlor but need CYA

    Yes this site is fantastic - I have learned so much and its a miracle the pool survived with me in charge until now

    Is plain CYA net acidic too?

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

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    Cherie's Avatar
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    Re: Scared of Trichlor but need CYA

    I'm sorry, Heather. I can't answer that one for you, since I've only had to add CYA once - and that was with the pool install last year. I've not had to deal with it, except to do some partial drains late last summer, after getting bad info from the pool store and ending up with our CYA being a bit too high. But I bet you'll find an answer to that if you utilize the "search" feature here on the site - I'm sure the gurus on here have answered that many times by now.
    32x16 buried Doughboy, 4' shallow - 7' deep
    Pentair Dynamo 1 hp, 2-speed - Pentair 150# SD40 w/zeolite (75#)
    One skimmer/two returns/Aquabot Turbo T2

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    Re: Scared of Trichlor but need CYA

    Quote Originally Posted by Solvangswimmers
    Is plain CYA net acidic too?
    Yes it is. Adding 30 ppm CYA would drop the pH from 7.5 to 7.14 in a pool with around a TA of 100 ppm.
    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"

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