A peritoneal dialysis system includes a disposable set, source(s) of concentrate(s), a water purifier, a sensor, and a control unit. The disposable set includes a water port, an inlet port, a drain port, a water line in fluid communication with the water port, a drain line in fluid communication with the drain port, and a container to hold a dialysis fluid prepared by mixing water and the concentrate(s). The source(s) of concentrate(s) are in fluid communication with the inlet port, and the water purifier is configured to purify water and feed the water towards the water port so the sensor can detect a fluid property. The control unit is configured to deliver dialysis fluid mixed in the disposable set to the drain line and water purified by the water purifier along the water line, into the disposable set, and out the drain line to push dialysis fluid to the sensor.
