Dialysis systems and methods

A dialysate delivery subsystem of a dialysis system, comprising:

• a water supply port in fluid communication with a source of purified water;
• a concentrate connection cap having an outlet line in fluid communication with the dialysis machine, the concentrate connection cap being configured to mate with at least one of the water supply port, a powdered bicarbonate canister, or a pre-mixed liquid bicarbonate concentrate container;
• wherein in a first configuration, the powdered bicarbonate canister is connected to the water supply port, and the concentrate connection cap is connected to the powdered bicarbonate canister, and wherein purified water is delivered from the water supply port into the powdered bicarbonate canister to form a mixed bicarbonate solution which is then delivered to the dialysis system via the outlet line of the concentration connection cap;
• wherein in a second configuration, the concentrate connection cap is connected to the pre-mixed liquid bicarbonate concentrate container, and wherein a mixed bicarbonate solution is then delivered to the dialysis system via the outlet line of the concentration connection cap;
• and
• wherein in a third configuration, the concentrate connection cap is connected directly to the water supply port, and wherein purified water from the source of purified water is configured to flow through the concentration connection cap to flush out residual concentrates.