Abstract: An exemplary embodiment of the invention includes a wastewater treatment plant having, in serial fluid flow relationship, a wastewater source, a wastewater treatment plant, and a discharge site. The wastewater treatment plant has, in serial fluid flow relationship, an aerobic bioreactor in fluid flow communication with the wastewater source and an anoxic bioreactor in fluid flow communication with the discharge site. Fixed film packing for growing microbes is disposed in first and second tanks of the first and second bioreactors, respectively. A primary holding tank is disposed between the wastewater source and the aerobic bioreactor. A first pump is used for pumping liquid out of the primary hold tank through a first pressure line into the first tank to a pressure line outlet in a bottom of the first tank.