Iron is one of the earth’s most plentiful resources, making up at least five percent of the earth’s crust. In well water iron is usually found in a dissolved state and may appear clear when first drawn from the tap.
The maximum amount recommended in water is 0.3 mg/L which is same as saying 0.3 Parts Per Million or PPM. When the level of iron in water exceeds the 0.3 mg/l limit, the water may have a red, brown, or yellow color and stain laundry and fixtures.
The water may also have a metallic taste and an offensive odor. Water system piping and fixtures can become restricted or clogged, and appliances such as water heaters, dishwashers and washing machines plugged with rust and sediment.
Iron gives water a disagreeable metallic taste. When the iron combines with tea, coffee and other beverages, it produces an inky, black appearance and a rusty, bad taste.
There are four main types of iron or conditions in which iron is found in well water:
- • Soluble “Clear Water” Iron
- • Insoluble Oxidized “Red Water” Iron
- • Organic Iron
- • Iron Bacteria
Questions to Ask When Choosing an Iron Filter:
1. What type of iron do I have in my water system?
2. What is the flow rate I have available, to backwash the iron filter I choose?
3. Do I have manganese, hydrogen sulfide odor, iron bacteria or tannin in my water?
4. What is the pH (acid or alkaline nature) of my water?
5. According to the water test results, will the water treatment unit remove the total iron concentration?
Test Your Water
If there is an iron problem with the water supply, the first step is to determine the source. The source of iron may be from the corrosion of iron or steel pipes or other components of the plumbing system where the acidity of the water, measured as pH, is below 6.8.
A water test will determine for iron, pH, manganese, hardness, and total dissolved solids is a good place to begin. If the water direct from the well has a yellow or tea colored look to it, an additional test for tannin is recommended as well. Take the sample as close to the well as possible.
With these results, you can identify if you need any type of water treatment, and what type of system to select, based on your water chemistry.
If the source of water is a public water system and you experience iron-related problems, it is important to contact a utility official to determine whether the red water is from the public system or from the home’s plumbing or piping.
Automatic Iron Filter Systems
For water very high in iron with high levels of hydrogen sulfide and/or manganese, we recommend a pre-chlorination feed for maximum removal rates. After the iron filter, many folks will use a carbon filter to remove any trace of the chlorine taste or odor.