Metal sequestrants will sequester the iron as the name suggests. BUT these do not remove the iron from the water! Whether you are doing AA treatment or sequestrants to get the brown stains to disappear, these are both temporary and you need to have a plan to remove the iron from the water. This could be with a water exchange, using Poly-fil, or some other method but stains will return if iron remains in the water.
I have used Natural Chemistry's Metal Free before where I just dumped in two bottles, with the brown stains disappearing immediately. Then within a week, the stains returned as soon as I brought up the FC level. So, yes sequestrants will help sequester the iron into the water but this is just temporary.
I deal with iron stains a lot and have "failed" multiple times because the stains return at some point. I fail less when I am able to make it 3-4 months without stains compared to 3-4 weeks. If you see my thread below, I was able to get a bunch of iron to precipitate to the Poly-fil which went into the trash. Even with that success, I am starting to see stains return. You just have to have a long term plan to frequently lower the iron content.
I was changing out the Poly-fil in my pvc pipe contraption and thought I would share the color of the Poly-fil to show it really does capture the iron. The brown that is constantly on my vinyl liner is very concentrated into the Poly-fil. The one clump which is kind of white was brown like the...
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