A method and system for water-priming carbon micropore filter media using negative pressure. The method includes placing dry filter elements in a polymer bag, applying a vacuum of no more than approximately 33 kPa above zero pressure, and heat-sealing the bag using a heat-set bar; submerging, by a consumer, the vacuum-sealed bag with its the filter elements in water; the filters in the vacuum sealed bag are at least partially submerged, puncturing the bag to form one or more small openings in the bag below the water line. Breeching the vacuum causes the water to flow through the openings into the bag and the filter(s) to equalize the pressure between the water and the previously vacuum environment of the plastic bag, causing the surrounding water to quickly flow into the micro-pores of the filter media, thereby priming the carbon filter for use in the gravity-fed water-purification system.