One of the most common water treatment problems found in well water is iron. Iron can be found in 3 different forms:
Ferrous iron (dissolved)
Although not visible it is the most common type of iron. Later when oxygen is mixed with ferrous iron it stains sinks, toilets and laundry especially when bleach is added. To reduce levels of ferrous iron, softening and or filtration is performed.
Ferric Iron (suspended)
Ferric iron or brown water iron is oxidized and forms particles. Normally these particles can be seen once settled down, the particles can be seen in a glass of water. Sometimes these particles are too small to be seen and very difficult to remove.
Iron bacteria is a general term given to iron that can leave a slimy growth or build up in toilet tanks and sometimes clogs filters, softeners and pipes. These bacteria are not harmful, but are considered a nuisance bacteria because of their difficulty in removing.