Aeration vessel and aerator assembly for use in a wastewater treatment system

In an aeration vessel used in an aerobic waste water treatment system, the aeration vessel having a bottom wall, a side wall and a top, a partition disposed in said aeration vessel, said partition having a downwardly opening mouth, said partition serving to divide said aeration vessel into an aeration chamber and a clarifier chamber, said clarifier chamber being located inwardly of said partition, the improvement comprising an aerator assembly extending into said clarifier chamber in said aeration vessel, said aerator assembly comprising a rigid tubular member having an upper end and a lower end, and a diffuser assembly, the diffuser assembly comprising a flexible connector and a diffuser head, the flexible connector connecting said diffuser head to said lower end and forming a fluid flow path between said diffuser head and said tubular member, said upper end being adapted to be connected to a source of an oxygen containing gas, said diffuser assembly having a weight sufficient to maintain said diffuser head generally parallel to said bottom wall.