A filter connection for peritoneal dialysis is presented including, in a flow line from a source of fresh dialysate solution carried on the patient's body, and under pressure, through a bacteria filter of sub-micron porosity for removing microorganisms generally greater than about 0.2 microns (nominal size) together with tubular connections leading from the filter toward a catheter inserted in the patient's peritoneum including in order from the filter, a first check valve permitting flow only away from the filter, then an outflow port with check valve permitting used dialysis flow only away from the patient, and finally the connection to the catheter tube.