A pure water system comprising: - a tank having an inner surface, an upper rim and a plurality of radial pins; - a cover assembly including a top cap having a lower rim and a plurality of bayonet slots that respectively receive the plurality of pins of the tank to secure the cover assembly and the tank to one another to form a fluid tight connection, wherein the number of bayonet slots corresponds in number, size, and position to the pins of the tank and wherein when the tank and cover assembly are rotated with respect to one another about a longitudinal axis of the pure water system a fluid tight engagement of the upper rim and the lower rim to one another is formed; - purification media disposed in a porous filter bag, the filter bag being positioned in and sealingly engaging the inner surface of the tank; and - the cover assembly comprising a release assembly, the release assembly having a pressure control plunger and a locking arm operatively coupled to a pivot lever secured to top cap for pivoting movement by a pivot axis, wherein the pivot lever is movable between a first position and a second position so that a single movement of the pivot lever from the first position to the second position vents pressure from the tank and unlocks the cover assembly from the tank, and wherein, when in the first position, the pressure control plunger forms a fluid tight connection with the cover assembly and the locking arm prevents removal of one of the plurality of radial pins from a respective one of the plurality of bayonet slots, and, when in the second position, the pressure control plunger vents the cover assembly and the locking arm allows removal of the one of the plurality of radial pins from the respective one of the plurality of bayonet slots, the release assembly further comprising a biasing member normally biasing the pivot lever to the first position with plunger seated against an underside of cap and locking arm extending through the cap into a slot with a side of the locking arm that abuts a locking pin to prevent the pin from being withdrawn from the slot, and in the second position, plunger has moved downward away from underside of cap a distance sufficient to allow pressure to vent from within pure water system and locking arm 68 has moved upward away from slot a distance sufficient to allow radial pins to be withdrawn from slots. - a tank having an inner surface, an upper rim and a plurality of radial pins; - a cover assembly including a top cap having a lower rim and a plurality of bayonet slots that respectively receive the plurality of pins of the tank to secure the cover assembly and the tank to one another to form a fluid tight connection, wherein the number of bayonet slots corresponds in number, size, and position to the pins of the tank and wherein when the tank and cover assembly are rotated with respect to one another about a longitudinal axis of the pure water system a fluid tight engagement of the upper rim and the lower rim to one another is formed; - purification media disposed in a porous filter bag, the filter bag being positioned in and sealingly engaging the inner surface of the tank; and - the cover assembly comprising a release assembly, the release assembly having a pressure control plunger and a locking arm operatively coupled to a pivot lever secured to top cap for pivoting movement by a pivot axis, wherein the pivot lever is movable between a first position and a second position so that a single movement of the pivot lever from the first position to the second position vents pressure from the tank and unlocks the cover assembly from the tank, and wherein, when in the first position, the pressure control plunger forms a fluid tight connection with the cover assembly and the locking arm prevents removal of one of the plurality of radial pins from a respective one of the plurality of bayonet slots, and, when in the second position, the pressure control plunger vents the cover assembly and the locking arm allows removal of the one of the plurality of radial pins from the respective one of the plurality of bayonet slots, the release assembly further comprising a biasing member normally biasing the pivot lever to the first position with plunger seated against an underside of cap and locking arm extending through the cap into a slot with a side of the locking arm that abuts a locking pin to prevent the pin from being withdrawn from the slot, and in the second position, plunger has moved downward away from underside of cap a distance sufficient to allow pressure to vent from within pure water system and locking arm 68 has moved upward away from slot a distance sufficient to allow radial pins to be withdrawn from slots.