Before deciding on a method to remove the iron, you need to know what the source of the iron is and what state the iron is in. Sometimes iron in your drinking water leaches from the pipes. This could be the source, or the pipes could increase the amount of iron that actually is in the well water.
The acidity of the water makes a difference in what will work to remove the iron, as does the amount of oxygen and carbonates available to the iron. Shallow groundwater and surface water provide enough oxygen to keep iron from dissolving in the water. If sulfur dioxide is available to the iron, the iron and sulfur will combine to form iron sulfide, which remains insoluble.
One other form of iron gives the appearance of reddish brown slime. This is caused by bacteria, not harmful to humans, that react with iron and change it from a soluble form to sludge, which precipitates from the water and accumulates in plumbing, water treatment equipment and toilet tanks.
You can remove iron with a water softener, which also removes calcium, magnesium and manganese. These minerals then must be removed from the exchange medium by a process called regeneration and backwashing. It is important to check the ratings for your unit, as some are able to treat water containing up to 10 PPM iron, but many are not. Suspended particles of insoluble iron, as well as iron sludge, will greatly reduce the effectiveness of the water softener unit and should be filtered out before water reaches the unit. Problems caused by iron bacteria can be eliminated by chlorinating the water and then filtering it.
A greensand filter, which contains glauconite, is an effective filter for removing soluble iron. The iron reacts with substances in the filter to form insoluble iron. This builds up on the filter and must be removed by backwashing, which should be done regularly. The greensand can be regenerated by washing with a permanganate solution. Most greensand filters are effective in treating iron concentrations up to 10 PPM, but if the water is acidic, the pH level will need to be raised above 7.0.
To decrease the acidity of your well water and raise the pH level, add an alkaline material, such as sodium carbonate, or pass the water through alkaline filters, such as calcite. If high salinity is a problem, it can be treated with reverse osmosis or distillation.
One alternative to treating the water is to drill deeper into the groundwater of the existing well.
Iron levels below 0.3 ppm usually cause no problems and can be beneficial.
Humans need iron to provide oxygen to the blood and normally excrete any excess rather than absorbing it into their systems.
Iron removal systems that require backwashing require flow rates of about 8 gallons per minute per square foot of filter bed.
Some people have an inherited condition whereby excess iron cannot be eliminated. For these individuals, drinking water high in iron content may be harmful.