The very existence of man depends on water. There is a misconception that it is better to consume water in its natural form. However, in order for natural water to be safe for drinking and suitable for household needs, it must be purified or processed. The cycle of water circulation in nature begins from the upper layers of the atmosphere (clouds). Falling to the ground in the form of rain or snow, water absorbs pollution and gases from the atmosphere. Getting to the surface of the earth, water seeps in and, flowing through the ground, dissolves minerals. For example, flowing through limestone, water dissolves calcium and magnesium salts. The acidity of the water (corrosivity) and the presence of dissolved iron and mechanical impurities in the water are also important problems.