A renal failure therapy system (10a, 10b) comprising: a renal failure therapy machine comprising: • a dialysis fluid circuit including a dialysis fluid pump (54, 58); and • a logic implementer; a source (86, 90) of physiological cleaning, disinfecting, and/or decalcifying substance in fluid communication with the dialysis fluid circuit, wherein the physiological cleaning, disinfecting, and/or decalcifying substance includes an acid; a source of purified water in fluid communication with the dialysis fluid circuit; wherein the logic implementer is in operable communication with the dialysis fluid pump (54,58), and is programmed: - to cause the physiological cleaning, disinfecting, and/or decalcifying substance to be added from its source (86, 90) to purified water from the purified water source to form a mixture, and - to circulate the mixture within the dialysis fluid circuit using the dialysis fluid pump (54,58) to at least one of clean, disinfect or decalcify at least a portion of the dialysis fluid circuit without a subsequent rinse after circulating the mixture and moving directly to a drain sequence, wherein to cause the physiological cleaning, disinfecting, and/or decalcifying substance to be added and to circulate the mixture being performed after a first treatment; characterized in that the logic implementer is programmed - to cause a portion of the mixture to be drained in the drain sequence, wherein draining a portion of the mixture from the dialysis fluid circuit includes trapping air in the dialysis fluid circuit, and - to cause a filling procedure for a second treatment to begin with the mixture remaining in the dialysis fluid circuit, the filling procedure relied upon to reduce the mixture remaining to a lower level and is used to remove a portion of the mixture to drain. a renal failure therapy machine comprising: • a dialysis fluid circuit including a dialysis fluid pump (54, 58); and • a logic implementer; • a dialysis fluid circuit including a dialysis fluid pump (54, 58); and • a logic implementer; a source (86, 90) of physiological cleaning, disinfecting, and/or decalcifying substance in fluid communication with the dialysis fluid circuit, wherein the physiological cleaning, disinfecting, and/or decalcifying substance includes an acid; a source of purified water in fluid communication with the dialysis fluid circuit; wherein the logic implementer is in operable communication with the dialysis fluid pump (54,58), and is programmed: - to cause the physiological cleaning, disinfecting, and/or decalcifying substance to be added from its source (86, 90) to purified water from the purified water source to form a mixture, and - to circulate the mixture within the dialysis fluid circuit using the dialysis fluid pump (54,58) to at least one of clean, disinfect or decalcify at least a portion of the dialysis fluid circuit without a subsequent rinse after circulating the mixture and moving directly to a drain sequence, wherein to cause the physiological cleaning, disinfecting, and/or decalcifying substance to be added and to circulate the mixture being performed after a first treatment; characterized in that the logic implementer is programmed - to cause a portion of the mixture to be drained in the drain sequence, wherein draining a portion of the mixture from the dialysis fluid circuit includes trapping air in the dialysis fluid circuit, and - to cause a filling procedure for a second treatment to begin with the mixture remaining in the dialysis fluid circuit, the filling procedure relied upon to reduce the mixture remaining to a lower level and is used to remove a portion of the mixture to drain. - to cause the physiological cleaning, disinfecting, and/or decalcifying substance to be added from its source (86, 90) to purified water from the purified water source to form a mixture, and - to circulate the mixture within the dialysis fluid circuit using the dialysis fluid pump (54,58) to at least one of clean, disinfect or decalcify at least a portion of the dialysis fluid circuit without a subsequent rinse after circulating the mixture and moving directly to a drain sequence, wherein to cause the physiological cleaning, disinfecting, and/or decalcifying substance to be added and to circulate the mixture being performed after a first treatment; characterized in that the logic implementer is programmed - to cause a portion of the mixture to be drained in the drain sequence, wherein draining a portion of the mixture from the dialysis fluid circuit includes trapping air in the dialysis fluid circuit, and - to cause a filling procedure for a second treatment to begin with the mixture remaining in the dialysis fluid circuit, the filling procedure relied upon to reduce the mixture remaining to a lower level and is used to remove a portion of the mixture to drain.