Ion exchanger is characterized by a great exchanging capacity – it effectively retains large amounts of iron. The ion exchanger can be regenerated and rinsed which makes this type of filtration very efficient and economical. A complete system comprises three columns. The column with hydro-anthracite bed works as a mechanical filter, the column with activated carbon removes organic matter and the column containing chelating resin selectively removes iron ions. If not removed, iron ions lead to bath pollution and necessity of its replacement.