An Atmospheric Storage Tank (AST) system designed to be an alternative to the existing RO pressure storage tank that operates on water pipeline pressure. It eliminates the disadvantage of subjecting the RO system to back pressure on the feed water which reduces the efficiency of the system and also has a higher probability of leakage. When the AST system is installed below the faucet, a pumping gadget is required to pump the water. It is primarily designed, although not exclusively, to be used together with a zero waste reverse osmosis system.