Embodiments of the invention provide a pumping system for at least one aquatic application. The pumping system includes a pump, a motor coupled to the pump, and a controller in communication with the motor. The controller determines a first motor speed, obtains a reference flow rate, determines a present flow rate, and determines a present power consumption. The controller calculates a difference value between the reference flow rate and the present flow rate, and uses at least one of integral, proportional, and derivative control to generate a second motor speed based on the difference value. The controller attempts to drive the motor at the second motor speed until reaching a steady state condition.