ANSWER: Oftentimes, iron may appear in a soluble (dissolved) or insoluble (precipitated) state in your water. To significantly reduce the iron, you may need to chlorinate or otherwise oxidize the iron such that it comes out of solution and is more easily filterable. An oxidizing iron filter is very effective. If your iron levels in your water aren't too high, a softener will be very effective at removing iron as well. Some suggest that you shouldn't rely on a softener as it tends to foul the ion exchange resins used to reduce unwanted constituents from your water, but others have experienced effective removal without negative side effects on waters with more than 25 ppm of iron using softeners.

If you're looking at a water quality analysis, soluble iron (also referred to as "clear water" iron) will be represented as Fe+2 (ferrous). Insoluble iron (also referred to as "red water" iron) will be represented as Fe+3 (ferric). Because iron can combine with other elements, it also can be present in an organic complex, which can appear as colorless, yellow or brown. A more daunting problem is when iron bacteria may also be present, which can create reddish brown or yellow slime, clog plumbing and cause a nasty odor that's fishy or oily. A rotten egg odor is generally associated with hydrogen sulfide (H2S), which can be associated with sulfate-reducing bacterias (SRBs) and is a whole other issue.