A renal therapy apparatus includes a blood filter, a blood pump, a treatment fluid pump, and a control unit configured to control at least one of the blood pump or the treatment fluid pump during a filter cleaning sequence. In a first phase of the filter cleaning sequence, a first fluid including a blood-compatible and physiologically safe fluid is transferred back and forth across the insides and/or outsides of the blood filter. After the first phase, a second fluid is formed by mixing the first fluid with air. In a second phase of the filter cleaning sequence, the second fluid is transferred across the insides and/or outsides of the blood filter at least one time.
