Kuyenda kosalekeza kwa madzi atsopano, osefedwa omwe amaperekedwa kudzera muzitsulo zitatu zosefera (activated carbon, ion exchange resin, ndi nsalu zopanda nsalu) zimalimbikitsa ziweto kumwa kwambiri, kulimbikitsa thanzi lawo lonse.Madzi oyendayenda amasefedwa nthawi zonse ndi okosijeni, zomwe zimapatsa kutsitsimuka kwakukulu.