What forms of iron might typically be found in a city’s water supply? In particular, what form of iron could cause my whole-house water filter, time after time over 2+ years, to turn a dark “rust” brown color within 2 to 3 weeks? Please see attached photo.
Our Pasco County, FL water, of course, meets the EPA limit of 0.3 mg/L iron, so what “other iron”, if iron is what I’m seeing, is causing this rapid? discoloration of my filter elements?
My store-bought test strips indicate iron at less than 0.3 mg/L, but are these strips only picking up “dissolved” iron, ie iron ions. If there are minute “flakes” of rust from iron pipes in the county’s water supply system, I’m guessing my test strips will not detect that iron, unless ions of iron migrate from the iron particles into the surrounding water.
Also, I have been told that if phosphates are used in the water treatment process, which is apparently not uncommon, that this can cause the rust colored “stuff” that my filter is capturing.
Obviously, I’m shooting in the dark here, but any explanations for what I’m seeing here will be much appreciated.
