A renal therapy blood cleansing system is provided. The renal therapy blood cleansing system includes a blood circuit including a blood filtering device, a therapy fluid circuit including a balance chamber configured to exchange like volumes of fresh and used therapy fluid, a first pump configured to pump fresh therapy fluid to the balance chamber, a second pump configured to pump used therapy fluid to the balance chamber, and at least one valve located downstream from the balance chamber, the at least one valve enabling fresh therapy fluid from the balance chamber to be directed selectively to (i) a flow path leading to an inlet of the blood filtering device, or (ii) a flow path leading to the blood circuit at a location upstream or downstream of the blood filtering device.