With Iron below 3ppm you could go with this system
Iron Reduction Whole House Water Filter Cartridge System by Pentek It will require a bit more maintenance than the other option I will give you, but it offers the advantage of low upfront cost. The other way to go is with something like this
Iron Whole House Water Filter W-410-CFA by American Plumber for Chemical-Free Iron Reduction Which requires alot less maintenance, but is more expensive up front.
Thank you,
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