We get more questions about iron than any other water problem. The method depends on how much iron is in your system and how fine the particles are. A test you can do yourself would be to fill a clear glass with water and let it sit for 15-20 minutes. If the iron settles to the bottom then a cartridge type filter (5 micron or smaller) should be able to remove the majority of the iron particles. If the particles remain suspended then a filter won't help.
For removal of very fine iron particles you will need either a water softener or an iron removal system. A water softener will remove up to 4ppm of iron, but if used this way the resin will need to be cleaned about once a month. If yours is higher than that then you will need an iron removal system with special media. Different media would be used for different mineral conditions. Sometimes aeration can be used. It's not necessarily better than ion resins, but you wouldn't need to regenerate the system with any chemicals. We highly recommend that you consult with a local expert before ordering any water treatment system.
This must be backwashed with some type of oxidizer. This can be hydrogen peroxide, chlorine, potassium permanganate, etc. (caution, some of these products can be hazardous in concentrated form). Of the above, hydrogen peroxide and potassium permanganate will not lose their properties as fast as most of them.
To avoid having to backwash, you could use Birm® media. However it requires a pH of 7 or above, and there can be no presence of hydrogen sulfide.
