Waturu Holding A/S has developed a new solution that, without the use of chemistry, can combat bacteria such as Legionella and p. Aeruginosa by utilizing the water's conductivity to briefly expose the bacteria to current. Bacteria are a continuous challenge in all domestic water installations and especially in properties such as hospitals and nursing homes, where the users have impaired immune systems or open wounds. Legionella is extremely important to fight, as the bacterium can cause legionary disease, which is a pneumonia that can be fatal. The problem in the fight against Legionella is that once the bacterium is present, the bacterium is almost impossible to kill. The bacterium can hide itself in the biofilm that is built up in the water installation and which sporadically detaches with the possibility of Legionella being able to "hide". As a standard method of combacting Legionella, an operating temperature of the hot water of more than 58 degrees C is used. Furthermore periods of flushing of the installation at higher temperatures are also done, which is difficult in a hospital with thousands of tapping points. Further methods used in the control are filtration as well as UV lighting, which is characteristic of being costly and requiring continuous replacement, as well as for UV lighting, it is useless if there is a release of biofilm in the water.