The invention concerns a device for generation of ion network for water treatment in tanks, especially for reduction of cloud and for stabilization of water surfaces, where the device is arranged on a floating body equipped with a drive for initiation of mutual motion of the floating body and water, whereas the floating body is equipped with an ejector and at least one source of electrolytically and/or photocatalytically treated water connected with an outlet (9) that leads into ejection and/or ejected water of an ejector.Eventually, an inlet of chemical agents (11) and/or an inlet of biological agents (12), an inlet of oxidation agent (13) or an inlet of air (14) lead into ejection and/or ejected water of the ejector.