Abstract: The invention provides a fluid distributor and associated water treatment system. The system includes a pressure vessel adapted and configured to hold a predetermined volume of fluid and a fluid distribution assembly. The fluid distribution assembly is preferably disposed at a lower end of the pressure vessel, and includes a water inlet manifold adapted and configured to direct water from an upstream location into a vessel that the distributor assembly is mounted into, a water outlet manifold adapted and configured to direct water from the vessel to a downstream location and an air volume control valve adapted and configured to maintain a predetermined pressure range in the vessel.