A wastewater treatment system for treating wastewater by processes which include aeration. The system includes an influent conduit for delivery of wastewater to be processed and a treatment tank for processing of the wastewater. Also included is an air conduit for providing compressed air for aeration of the wastewater and a particle size regulation device disposed between the conduit and the tank, wherein the particle size regulation device regulates a size of particles present in the wastewater to provide particle size regulated wastewater. The system also includes at least one aeration jet having a nozzle diameter sized to allow the particle size regulated wastewater to pass through the nozzle.