Abstract: Systems, devices, and methods of filtering water utilize an integrated gravity-fed, dual ion-exchange filtration bottle. Flow-through multi-stage filtration technology is applied to a personal water bottle. The system filters water from an upper unfiltered water reservoir through a multi-stage filter to a lower filtered water reservoir. A user then drinks from the lower reservoir. The bottle includes a cap with a filtered water outlet through which filtered water in the lower reservoir is accessed with a straw, spout, or other access device. The cap includes an unfiltered water inlet to allow filling and refilling of the upper reservoir without disassembling the bottle. The bottle includes a filter vent that eliminates air locks and partial vacuum that can develop when unfiltered water drains from the upper reservoir through the filter to the lower reservoir. This gravity-fed dual ion-exchange filtration system allows for more complete removal of dissolved solids.

Abstract: Systems, devices, and methods of filtering water utilize an integrated gravity-fed, dual ion-exchange filtration bottle. Flow-through multi-stage filtration technology is applied to a personal water bottle. The system filters water from an upper unfiltered water reservoir through a multi-stage filter to a lower filtered water reservoir. A user then drinks from the lower reservoir. The bottle includes a cap with a filtered water outlet through which filtered water in the lower reservoir is accessed with a straw, spout, or other access device. The cap includes an unfiltered water inlet to allow filling and refilling of the upper reservoir without disassembling the bottle. The bottle includes a filter vent that eliminates air locks and partial vacuum that can develop when unfiltered water drains from the upper reservoir through the filter to the lower reservoir. This gravity-fed dual ion-exchange filtration system allows for more complete removal of dissolved solids.