In some examples, a filtration assembly for hemodiafiltration therapy includes a filtration body connector configured to removably mechanically connect the filtration assembly and a dialyzer. In examples, the filtration assembly is configured to remain substantially stationary relative to the dialyzer when the filtration assembly mechanically mates with the dialyzer. The filtration body connector is configured to removably mechanically connect the filtration assembly with a plurality of different types of dialyzers, which may be selected based on a prescription for a particular patient.