A water filter is a device which removes impurities from water by means of a fine physical barrier. Filters are used to cleanse water for drinking water, aquariums etc. Water filters can be used for preventative health reasons in the case of harmful substances, to improve the taste, colour or odour of drinking water. Domestic water filters can be attached directly to a tap, attached to the domestic water supply before the tap, or filters can be used at the point of use or in a portable unit.
