A reciprocating fluid pump includes a pump body, a subject fluid chamber, a first plunger located within the subject fluid chamber of the pump body and having a first head portion and a first bellows, the first plunger configured to expand and compress in a reciprocating action to pump the subject fluid through the subject fluid chamber within the pump body, wherein the first head portion and the first bellows have a first cross-sectional dimension, and a second plunger located within the subject fluid chamber of the pump body and having a second head portion and a second bellows, the second plunger configured to expand and compress in a reciprocating action to pump the subject fluid through the subject fluid chamber within the pump body, wherein the second head portion and the second bellows have a second cross-sectional dimension that is smaller than the first cross-sectional dimension.