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Thread: Low TA and green water

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    Low TA and green water

    I've read where low TA values can react with the iron in your water and tint it green. Not due to algae problems, but the low TA chemistry reacting with the iron. Has anyone have any experience with this?
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    JasonLion's Avatar
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    Re: Low TA and green water

    It is possible for metals in the water to turn the water a clear transparent green, though it is rare and has nothing in particular to do with low TA values. Usually it is triggered by adding chlorine.
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    Re: Low TA and green water

    It could be that a lower TA results in a greater rise in pH when chlorine is added and the combination of the chlorine plus the higher pH causes the metal (usually copper if it's green) to show up. As Jason noted, the TA itself isn't the cause, but the rise in pH when adding a hypochlorite source of chlorine (chlorinating liquid, bleach, Cal-Hypo, lithium hypochlorite) is more extreme when the TA is lower. On the other hand, a very high TA can lead to a pH rise all on its own even without adding chlorine so you can see that it's really the pH that is a key cause of metal staining/precipitation/coloration.
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    Re: Low TA and green water

    Quote Originally Posted by JasonLion
    though it is rare .
    I'm actually not so sure it's that rare. Several have reported on here that they see green water thats basically clear after adding chlorine and after some dectective work, figured out it was iron.
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    JasonLion's Avatar
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    Re: Low TA and green water

    Well, there is rare and then there is rare. We hear about this several times a year, but it doesn't begin to compare to the number of times someone says their pool is green and it is actually algae. So it isn't rare in the sense of "I heard of that happening once ten years ago" kind of way, but it is rare compared to the number of times a pool turns green because of algae.

    The two, algae green and metals green, are often mixed up on the forum, even though they look totally different. People just say green and it isn't obvious what they mean by that. So, if someone says their pool is green then it is 99% that it is algae and only 1% that it is metals, which is one kind of rare.
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    Re: Low TA and green water

    I guess it depends on what the definition of rare is. Kinda like what the definition of "is" is
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    Re: Low TA and green water

    OK.... so if it is metals green, what is the suggested way to clear things up?
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    Re: Low TA and green water

    Quote Originally Posted by LWillis
    OK.... so if it is metals green, what is the suggested way to clear things up?
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