Abstract: An assembly for use in a well containing a mixture of hydrocarbons and water wherein the assembly separates hydrocarbons or relatively lighter fluids from the mixture and injects water or relatively heavier fluids into the well. The assembly includes an upper pump that pumps the relatively lighter fluids to the surface. A tandem pump is positioned below the upper pump for pumping well fluids down to a downhole separator. An oil bypass tube is provided in communication with the tandem pump for transferring the relatively lighter fluids to the upper pump, for subsequent pumping to the surface. A recycle tube is also provided that communicates with the downhole separator and the tandem pump for transferring at least a portion of the relatively heavier fluids from the downhole separator to the tandem pump, for pumping the relatively heavier fluids back to the separator.