The abundance and relative purity of ground water guarantees its increase in usage. In some localities, the content of iron and manganese in ground water is so high that these metals must be removed before the water can be used for drinking or industrial purposes. The Vyredox method developed in Finland and used now also in Sweden and some other countries oxidises the ferrous ion (which is soluble in water) to the ferric ion (which is insoluble), before the water enters the well, making use of iron-oxidizing bacteria and aeration wells.
HALLBERG, R.O. ; MARTINELL, R. (2006): Vyredox - In Situ Purification of Ground Water. In: Ground Water: Volume 14 , 88-93. URL [Accessed: 21.11.2012]