The invention provides a carbonation tank assembly for admixing a gas and a potable liquid used in preparation of drinks. The assembly includes a tank body with an interior that can be easily accessed for cleaning and repair purposes by removing upper and lower end plates securely and sealing fitted by gaskets to the upper and lower ends of the tank. The interior is connected to a liquid source for supplying liquid, a gas source for carbonating the liquid, and drawing means for dispensing carbonated liquid from the interior of the tank.