A refill unit for a fluid container is providing. The refill unit has a housing defining a fluid path in fluid communication with an outlet and configured to be operatively engaged with the fluid container, a fluid reservoir having an ejection port arranged in fluid communication with the fluid path inside the housing, and an ejector assembly configured to incrementally eject between 6 ml and 50 ml per increment of fluid from the reservoir when the assembly is actuated by operative engagement of the fluid container with the housing.