Water filtration system, namely, filtering or purifying machinery and apparatus and their components for filtering or purifying water. Water treatment components - RO (Reverse Osmosis) membranes and filters, which are installed indoors and are hydraulically, electronically or electrically controlled. Cartridge water filters, water filtering membranes, and their housings for the membranes and filters. Purifying systems for water pre-treatment, treatment and filtration for domestic, commercial, and industrial use. Water treatment equipment which is installed indoors and is hydraulically, electronically or electrically controlled by cartridge filtration units and/or reverse osmosis