Water treatment system for swimming pool water

In a swimming pool water treatment system for removal of iron from a supply of incoming water containing a quantity of dissolved iron, the system comprising:

• (a) a storage vessel having a capacity of predetermined volume;
• (b) a feed water input for receiving iron containing feed water and an output for delivering treated water therefrom, with said feed water input and said treated water delivery each being at a certain first predetermined volumetric flow rate;
• (c) a branch injection/filtration circuit operatively coupled to said storage vessel through upstream removal and downstream return ports, and including pumping means for continuously maintaining a flow of water through said branch injection circuit at a certain second predetermined volumetric flow rate;
• (d) said injection/filtration circuit including injector valve means for metered injection of a controlled quantity of an alkali metal hypochlorite to said treatment flow upstream from said return port;
• (e) filtration means between said removal port and said injection site for removal of insoluble iron precipitated during contact dwell time within said storage vessel;
• (f) the volumetric rate of said second flow exceeding that of said first flow by a magnitude of at least about 8:1 for maintaining the concentration of hypochlorite within said storage vessel, and with the predetermined volume capacity of said storage vessel being at least about 50 times the per minute volume of said first predetermined volumetric flow rate.