Before and After Ascorbic Acid Treatment (Iron Stains)


May 9, 2022
Folsom CA
I had what I started suspecting to be iron stains. I asked for help identifying them. @mknauss recommended me to try the tests here: Stains in Your Pool. Here is my original post: Is this iron staining?

The tests all but confirmed much of the staining was at least from iron. (Side note: I used Emergen-C packets for the ascorbic acid test--they work!).

Thus, I performed the ascorbic acid treatment as outlined here: Ascorbic Treatment to rid Pool of metal stains. Some of the specifics of the protocol were a tad unclear (especially what "slowly" means in regard to raising chlorine levels). But that is a minor nuance. I chose to interpret that as a couple days. Used polyquat 60 to keep away algea while FC was zero.

The treatment was a tremendous success. While my plaster doesn't look 100% by any means (previous owner neglect), it is massively improved and I suspect the rest of the staining is copper and/or other plaster defects.

Before photos named "before."

After photos named "after."

Thanks to everyone who contributed to this info!


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