Fanless and filterless, it makes no sounds and needs no maintenance, but you should remember to clean from the ionized dust that builds up close to it within the wall. Alongside with elevating the pH stage, a water ionizer machine must also remove any contaminants or toxins from the water. https://allhealthmarket.com/product/home-care-2/oxygen-and-hydrogen-generator/hydrogen-inhalation-machine-300ml-450ml-inhalation-machine-molecular-oxygen-hydrogen-generator-h2-inhaler-water-ionizer-spe-pem/