A well pump assembly has an upper plunger and a lower plunger. A working fluid conduit extends between the upper and lower plunger. An upper piston in the working fluid conduit is connected with the upper plunger. A lower piston in the working fluid conduit is connected with the lower plunger. A downstroke working fluid is located between the upper and lower pistons in the working fluid conduit. An upstroke conduit extends between an upper port in the working fluid conduit above the upper piston and a lower port in the working fluid conduit below the lower piston. An upstroke working fluid fills the upstroke conduit and the working fluid conduit above the upper piston and below the lower piston.
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