Abstract: A polymer mixing/activation system comprising a liquid inlet line, a polymer inlet line, a mixer-ejector, an ejector outlet line, and a mixing/retention chamber. The liquid inlet line is connected to a source of pressurized liquid, such as a city water line. The polymer inlet line is connected to a source of emulsion polymer which, when mixed with the liquid and activated, forms a liquid/polymer solution suitable to attract, coagulate or flocculate suspended solids in a fluid, such as waste water. The liquid inlet line and the polymer inlet line are connected to the mixer-ejector. The mixer-ejector has passageways arranged and shaped so that when the liquid flows therethrough, a suction is created which draws the polymer into the mixer-elector and simultaneously mixes the polymer with the liquid to form a liquid/polymer mixture.