Cooling water circuits can be found in a range of industries all over the world. Normally circulatory cooling conditioned water is used where fresh water is not possible. Cooling water consumption is minimized and the whole system must be protected from corrosion, sediment and growth of biological organisms, which can lead to serious diseases such as Legionella: prevention has become the prime concern. Blow down operations prevents scaling and corrosion. Chemically conditioning of the make-up water by adding biocides thus disinfecting the water from germs and the growth of algae or biological organisms.