Aeration Industries – Aire-O2 Aspirator This surface aerator creates a vacuum drawing air down the shaft into the water. The rotating propeller forces water outward horizontally past the end of the shaft at high velocity. Above the water line, atmospheric air is drawn through intake ports and travels through the hollow drive shaft to be dispersed in a large plume throughout the water. Being diffused into fine bubbles – about 2.0 mm diameter – the oxygen has extended contact time with the water. The size of the plume varies with the size of the aspirator/aerator which can be from two to 100 HP. Properly positioned, these units can create a “flow linkage” that delivers mixing and oxygen dispersion evenly and thoroughly throughout an entire basin regardless of its size or shape. Dead spots are eliminated.