Various embodiments of a semiconductor processing fluid delivery system and a method delivering a semiconductor processing fluid are provided. In aspect, a system for delivering a liquid for performing a process is provided that includes a first flow controller that has a first fluid input coupled to a first source of fluid and a second flow controller that has a second fluid input coupled to a second source of fluid. A controller is provided for generating an output signal to and thereby controlling discharges from the first and second flow controllers. A variable resistor is coupled between an output of the controller and an input of the second flow controller whereby the output signal of the controller and the resistance of the variable resistor may be selected to selectively control discharge of fluid from the first and second flow controllers.