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Thread: Should I start Saturday morning or wait 'till dark to shock?

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    Should I start Saturday morning or wait 'till dark to shock?

    If I can get the water circulating correctly (don't ask), I could start dumping chemicals in this morning. It's going to be hot and sunny here. Is it really bad to start during the day? I'd like to have as much time as possible to monitor and adjust before I have to go back to work on Monday. The pool was not opened last year and it is very green. Thanks!
    40K gallon plaster, S8M150 sta-rite system 3 cartridge filter, Paramount infloor cleaning system with 9 port and debris canister, Pentair pump.

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    BoDarville's Avatar
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    Re: Should I start Saturday morning or wait 'till dark to sh

    If you have the time to monitor the pool and check FC throughout the day, I would start now and as early in the AM as possible. I'm a little concerned about what you mean by "If I can get the water circulating correctly". The pump should be on 24/7 during the Shock Process. Also, I would lower the pH to around 7.2 before you begin the Shock Process, then ignore it until you are done and FC drops below 10 ppm. I am assuming you know what your CYA is as that will determine your FC target.
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    Re: Should I start Saturday morning or wait 'till dark to sh

    I had some leaks. Just bought the house last summer and just getting to the point of checking things out now.

    Roger on the ph. It's 9.5! There were some "ph increaser" granules here. I plan to mix with water and dump in. Have not mesured the cya or other stuff yet but I got the tft test kit so I'll be set. I'm assuming I can deal with the PH before doing the other tests?
    40K gallon plaster, S8M150 sta-rite system 3 cartridge filter, Paramount infloor cleaning system with 9 port and debris canister, Pentair pump.

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    Richard320's Avatar
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    Re: Should I start Saturday morning or wait 'till dark to sh

    Quote Originally Posted by neato5oh
    I had some leaks. Just bought the house last summer and just getting to the point of checking things out now.

    Roger on the ph. It's 9.5! There were some "ph increaser" granules here. I plan to mix with water and dump in. Have not mesured the cya or other stuff yet but I got the tft test kit so I'll be set. I'm assuming I can deal with the PH before doing the other tests?
    Is that a typo? What tester reads that high?

    And if that's correct, you need pH decreaser aka acid.

    But, that said, if pH is corrected and pump is working, start today. It's a lot easier to retest and replenish the chlorine every couple hours while you're up and awake.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

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    Re: Should I start Saturday morning or wait 'till dark to sh

    yep - typo. It's sodium bisulfate. If I go through that I guess I'll head to home depot for muriatic acid?
    40K gallon plaster, S8M150 sta-rite system 3 cartridge filter, Paramount infloor cleaning system with 9 port and debris canister, Pentair pump.

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    Richard320's Avatar
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    Re: Should I start Saturday morning or wait 'till dark to sh

    Quote Originally Posted by neato5oh
    yep - typo. It's sodium bisulfate. If I go through that I guess I'll head to home depot for muriatic acid?
    Yep. Check the pool aisle first for the good stuff, 31.45%. Sometimes the stuff in paint is "fumeless" or whatever which is a euphemism for diluted.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

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    Re: Should I start Saturday morning or wait 'till dark to sh

    Well I dumped about 8 lb's of the "ph decreaser" in and the ph is still 9.5 (testing with the tft kit it's 8.2, but testing with the hatch kit I have for my well water it's 9.5). Does that stuff go bad? Am I missing something?

    Wondering how many gallons of muriatic acid it's going to take to get the ph to budge?
    40K gallon plaster, S8M150 sta-rite system 3 cartridge filter, Paramount infloor cleaning system with 9 port and debris canister, Pentair pump.

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    Richard320's Avatar
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    Re: Should I start Saturday morning or wait 'till dark to sh

    Quote Originally Posted by neato5oh
    Well I dumped about 8 lb's of the "ph decreaser" in and the ph is still 9.5 (testing with the tft kit it's 8.2, but testing with the hatch kit I have for my well water it's 9.5). Does that stuff go bad? Am I missing something?

    Wondering how many gallons of muriatic acid it's going to take to get the ph to budge?
    Sounds right.

    PH is logarithmic..9.5 to 8.5 is ten times the jump that 8.5 is to 7.5. So it will take a lot of acid to get things down. Even the pool calculator carries this disclaimer
    Results are approximate and can be off significantly for large pH changes.

    To get a pool as big as yours from 8.2 to 7.5 will take 2 gallons! I'd just add a gallon at a time and give it an hour circulating between jugs with a little brushing to be sure the dead spots get stirred up until the pH dips below 8.2 somewhere. Then start measuring the doses.

    Note that the TA level affects the acid demand, too.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

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    Re: Should I start Saturday morning or wait 'till dark to sh

    hmmm... maybe I didn't wait long enough for that other stuff to kick in? I'll recheck after I get back from my acid trip.

    Just measured the TA and it is 50.
    40K gallon plaster, S8M150 sta-rite system 3 cartridge filter, Paramount infloor cleaning system with 9 port and debris canister, Pentair pump.

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    Re: Should I start Saturday morning or wait 'till dark to sh

    ... is that a good TA? Should I try to adjust that? I have a bunch of baking soda...

    Or should I do the PH first.

    BTW - thank you VERY much for your help!
    40K gallon plaster, S8M150 sta-rite system 3 cartridge filter, Paramount infloor cleaning system with 9 port and debris canister, Pentair pump.

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    Richard320's Avatar
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    Re: Should I start Saturday morning or wait 'till dark to sh

    Quote Originally Posted by neato5oh
    ... is that a good TA? Should I try to adjust that? I have a bunch of baking soda...

    Or should I do the PH first.

    BTW - thank you VERY much for your help!
    I'd save it. You'll probably be losing water when you backwash the filter as you're clearing the green. No point adding TA only to pump it out a few hours later. It's easy to fix once the pool is clear - you have the baking soda already.
    16K freeform gunite with spa; Pentair 4000 DE filter; Century Whisperflow 1 HP; Pentair Minimax heater.
    Troublefree does not mean Maintenancefree. It's like brushing your teeth: You can spend a couple minutes a day and pennies a week or go to the dentist once a year and spend several thousand dollars.
    A pool is like a pet - you have to feed it every day, even the days you don't want to play with it!

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    Re: Should I start Saturday morning or wait 'till dark to sh

    OK - so I dumped in 2 gallons of acid (31.5%) and the PH is now 6.5. Going to try adding baking soda to try to make it go back up.
    40K gallon plaster, S8M150 sta-rite system 3 cartridge filter, Paramount infloor cleaning system with 9 port and debris canister, Pentair pump.

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