A high-capacity pump fabricated with improved motor cooling and corrosion resistant components and powered by a variable-speed brushless DC motor suitable for use with a wide variety of applications. A brushless 12V DC motor is controlled by a manual and wireless variable speed control means to provide unparalleled flow control. The motor is contained within the housing in a sealed cavity in the housing, wherein the cavity is filled with mineral oil which maximizes heat transfer to facilitate motor cooling. A PVC impeller is contained within a PVC section of the housing thereby creating a corrosion resistant impeller section. The pump of the present invention has achieved improved performance over known pumps and is capable of delivering 4,500 gallons per hour (GPH) at 6 feet of head pressure, while only drawing 30 amps at 12 Volts DC. Wireless remote control of the pump is achieved via a wireless enabled device.