A cartridge for selectively dispensing an additive to water that includes a housing, a bladder disposed within the housing, and a pump connected to the housing and in fluid communication with the bladder. The bladder is configured to contain a consumable additive such as a flavor, for water. The pump is operable to selectively dispense an amount of the additive into water. The cartridge may be connected to a water filtration system such that the cartridge may dispense the additive into filtered water.