Abstract: A water treatment tank for use in a water treatment or softening system is disclosed which is operative in a treatment mode to receive untreated water through an inlet port and to pass treated water through an outlet port, and which is operative in a backwash mode to receive wash water through the outlet port and to pass waste water through the inlet port. Treatment tank has a vessel having an interior cavity which is partitioned into a top headspace portion, and a middle treatment bed space portion, and a bottom headspace portion via the placement of a pair of distributor filters mounted within the interior cavity to extend between the side walls thereof. The filters are spaced-apart, respectively, from the top end wall to define therewith the top headspace portion and the bottom headspace portion.