A method is provided for reducing scale inhibitor demand for protecting an electrical submersible pump (ESP) for downhole service in a wellbore. The method includes performing an SIS treatment through the ESP. The ESP includes a motor comprising a housing that houses a motor stator and a pump intake coupled to a pump stage. The pump stage includes an impeller; and a diffuser. The pump stage is coupled to the motor stator. A hydrophobic coating substantially covers each surface of the motor, motor stator, housing, pump stage, impeller, and diffuser, that is in direct contact with fluids in the wellbore. The method further includes monitoring the concentration of the scale inhibitor in the produced fluids; and repeating the SIS treatment through the ESP when the scale inhibitor concentration falls below a minimum effective dose (MED), wherein the MED is decreased by the hydrophobic coating by about 20% to about 80%.