Installation, maintenance and repair of water filtration systems, water softeners, deionization systems, well water systems, sulfur water treatment systems, iron water treatment systems, drinking water filtration systems, reverse osmosis systems, water bacteria removal systems, air purification systems, air bacterial filtration; Providing information relating to the repair or maintenance of water purifying apparatus; Providing information related to the installation, maintenance and repair of water filtration systems, water softeners, deionization systems, well water systems, sulfur water treatment systems, iron water treatment systems, drinking water filtration systems, reverse osmosis systems, water bacteria removal systems, air purification systems, air bacterial filtration; Maintenance of water purifying apparatus