The invention relates to a device for the decontamination of water, particularly of heavy metals andor arsenic andor their compounds, by means of electrolysis, wherein the water to be purified is fed through a receptacle and passes by electrodes of different polarities. Flat wire pairs with conductive covers and symmetrically placed shield conductors in grooves between flat wires minimize intra-pair signal flow skew. First, the brackets are provided with a shelf engaging recess. Each histogram may be divided, as an example, into two portions. The apparatus is effective in providing a desired scattering ability without increasing a drive voltage.