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Thread: Trouble balancing pool after ascorbic acid treatment

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    Trouble balancing pool after ascorbic acid treatment

    Folks -- ascorbic acid treatment went great. Iron stains lifted like magic.

    So I used Poly60 to hold off algae and that went okay. So I started adding Chlorine back and the pool turned iron yellow/brown. So I added a modest amount of ascorbic acid back to the pool and bang, it went away.

    I've been struggling to raise chlorine levels without getting the water to start turning brown again. And I've been fighting algae as a result.

    What's the trick? What am I doing wrong in terms of bringing free chlorine levels back up without the pool turning funky colors?

    Thanks!
    15,000 gal SWG pool, cartridge filter, all pentair equipment, variable speed pump, 400K BTU heater and spa, pebbletec finished

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    Mod Squad zea3's Avatar
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    Re: Trouble balancing pool after ascorbic acid treatment

    You need to add sequestrant before you start bringing the FC up. Or if you have a source of iron free water you could drain and refill. If that is not an option get a good sequestrant based on HEDP, phosphonic acid, or phosphonic acid derivatives and follow the directions for adding it to the pool. You will need to add sequestrant regularly to prevent the stains from coming back.
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    Re: Trouble balancing pool after ascorbic acid treatment

    Quote Originally Posted by zea3 View Post
    You need to add sequestrant before you start bringing the FC up. Or if you have a source of iron free water you could drain and refill. If that is not an option get a good sequestrant based on HEDP, phosphonic acid, or phosphonic acid derivatives and follow the directions for adding it to the pool. You will need to add sequestrant regularly to prevent the stains from coming back.
    I've tried to avoid phosphate containing sequestrant and instead using non-phosphate ones. Possible with those to achieve the same? I have a pool with a lot of organic material anyways, so I try and keep the phosphates in check to avoid algae (though I know that view is not entirely popular on this board ).

    Thanks!
    15,000 gal SWG pool, cartridge filter, all pentair equipment, variable speed pump, 400K BTU heater and spa, pebbletec finished

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    Mod Squad zea3's Avatar
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    Re: Trouble balancing pool after ascorbic acid treatment

    I don't know if another type of sequestrant will work as well. If you keep the chlorine high enough the phosphates are not going to be a problem. If you don't use an effective sequestrant you won't be able to raise the FC high enough to prevent algae without causing the iron to come out of suspension and stain the pool.
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    Re: Trouble balancing pool after ascorbic acid treatment

    Is it possible to use a chemical like ProTeam Metal Magic which converts the dissolved metals in the water into insoluble metal particulates which are then captured in the filter?

    I've seen it mentioned in a few threads on TFP but don't know much about its effectiveness and impact on a filter (you might need to replace cartridges when done treating the water).

    It might lower the over metal concentration in the water to make it easier to raise the chlorine back up again.


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    Re: Trouble balancing pool after ascorbic acid treatment

    Quote Originally Posted by jeffbg View Post
    I've tried to avoid phosphate containing sequestrant and instead using non-phosphate ones. Possible with those to achieve the same? I have a pool with a lot of organic material anyways, so I try and keep the phosphates in check to avoid algae (though I know that view is not entirely popular on this board ).
    If you are keeping phosphates low to prevent algae, presumably because you want to have a lower FC/CYA ratio than recommended here at TFP or you have recurring yellow/mustard algae or you just want more insurance because you don't think you can maintain the appropriate FC/CYA level, then yes you wouldn't want to add phosphates to the pool via an HEDP-based metal sequestrant. The issue is that HEDP is somewhat resistant to chlorine breakdown, unlike EDTA for example, so you'd have to find a non-phosphate metal sequestrant that both sequestered well and didn't break down too quickly from chlorine. Though that may exist, we don't know of a particular brand that does that well.
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    Re: Trouble balancing pool after ascorbic acid treatment

    I am a newbie and just successfully completed the AA treatment for iron stains that had built up over the last 2-3 years; I always attributed the stains to the neighbors' two oak trees that almost overhang into my pool. If you have oaks, you know what I am dealing with. I have a salt pool with a salt generator (swg) and after I completed my AA treatment, i used Jacks Purple stuff as the sequestrant. I have no idea what this stuff is but my pool looks great and it helps keep it 100% stain free. In my case, i added about 150% more of the Jack's than I needed to help keep stains from returning; i figured more was better with this stuff and since i know i have the phosphates anyways with the oaks, oh well.

    From what i can gather, phosphates are a non issue IF you keep your cl in line with your CYA. You haven't been read the riot act yet but until you post your numbers, the advice here is going to be limited to what your specific pool parameters are. First thing i did was buy my taylor k2006 and i love this tester and knowing my pool parameters has made the info on this site invaluable to the way my pool looks now.

    In my case, I have a serious CYA level of 150 so I have to keep my chlorine up and at the same time balance it so it's not too high to redeposit the stains. Jacks purple stuff has phosphates but as chem geek has pointed our over and over in his posts, it's a non-issue if you keep your cl in line, phospates can't feed algae if you have chlorine in the pool. yes Jack's is more money, but hey, isn't that what a pool is for, to throw money into?

    Finally, as to your re-staining issue, that wasn't my issue. After the AA, mine was cloudy water. This lasted almost 2 weeks and I was really getting worried. I drank a lot of wine to have patience (thanks JasonLion), back-washed almost everyday and added bleach at a really really slow rate (don't use scented/non-splash). I was able to do this b/c of the algcide i added before starting the AA treatment. My pool finally cleared and I am still balancing cl/ph/jacks/and filter run time. I think after an AA treatment, each pool is going to be different and it sounds like a pool drain for you or paying the extra monthly expense for a good sequestrant; w/o which your stains will probably return. What i got from this site was patience in adding the cl and giving the process time to work.
    I live in SoCalif so a pool drain per wife is out of the question; Jacks it is!
    Good luck
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