Abstract: A continuous cycle peritoneal dialysis system which includes a source (14) of dialysis fluid, and an inflow line (34) and outflow line (35) connected to a catheter (26) implanted in the peritoneal cavity (28). A fill pump (B) pumps dialysis fluid from the source to the catheter during a fill cycle. A drain pump C pumps fluid from the catheter to a drain during a drain cycle. A function of a volume of the dialysis fluid in the peritoneal cavity is detected by a manometer (D). A process controller (A) controls the fill and drain pumps in response to signals from a high fluid level detector (50) and a low fluid level detector (52) on a fluid column tube (48) to pump a calibrated fill volume of fluid into the cavity and a calibrated drain volume of fluid out of the cavity continuously in alternating fill and drain cycles in a manner that the fluid flows through the cavity generally with zero dwell time.