... bottom aerators dissolved oxygen content≥four 1.5KW waterwheel type or float type aerator of dissolved oxygen.2, low cost, save ... change or not to change water, promoting the environmental protection type culture of.4, vitality is strong, reduce the disease ... , 5.5 kilowatts, 7.5 kW). UPC50 supervisor, tank, saddle type connectors, nylon three through and through. The microporous aeration head ...