Abstract: A wastewater treatment system is provided which includes (a) two chambers in which microbiological cultures grow aerobically, a first chamber which receives wastewater to be treated and a second chamber which produces activated sludge; (b) a float sludge separator for removing from the system float sludge made with the aerobic culture from the first chamber; and (c) an activated sludge separator for separating activated sludge, which is settleable, and treated wastewater from the aerobic culture in the second chamber. In the system, one portion of the activated sludge from the activated sludge separator is fed to the first chamber, to seed culture growth there, and another portion of the activated sludge is recycled to the second chamber, to seed culture growth there.