A maple sap reverse osmosis system that comprises a feed pressure pump configured for receiving maple tree sap, a filter bank, at least one pressure pump operatively connected to the feed pressure pump through the filter bank, at least one recirculation pump operatively connected to the at least one pressure pump, each recirculation pump having an associated housing having an input positioned at a bottom portion of the housing, a permeate output and a concentrate output, the housing enclosing a membrane producing permeate and concentrate from the maple sap and an air inlet operatively connected to a housing in a exit position. The housings are serially connected from an entrance position housing to the exit position housing through associated inputs and concentrate outputs and wherein the housings can be completely drained of liquid through the input of the entrance position housing.
