Abstract: Electrostatic filters, systems and methods having separate positively and negatively charged filter elements within electrically isolated filter tanks for electrostatically filtering particles from a fluid flow. Both positive charged connections biased to earth ground and negative charged connections biased to earth ground are made to the respective positive and negative charged filter elements, along with triboelectric induced charge accumulations from the fluid flow, for separating charged particles within the fluid flowing parallel through these oppositely charged filter elements. Variable resistors of a power supply connected to such filters, systems and methods provide for controlling and adjusting for any undesired voltage excesses and/or shortfalls within these filter tanks so that the fluid flowing exiting these filter tanks is unbiased to generate a filtered fluid having balanced electrostatic charges.