An apparatus for extracorporeal blood treatment comprising a filtration unit, a blood circuit comprising a blood withdrawal line and a blood return line, and a fluid circuit. The fluid circuit comprises at least one or more water inlet ducts for receiving water, a dialysis preparation assembly comprising one or more concentrated sources housing a respective concentrate solution and configured to prepare a mixed solution of a dialysis fluid, wherein the water inlet duct is configured to provide water to the dialysis preparation assembly for preparing said mixed solution of dialysis fluid. The fluid circuit further comprises an infusion preparation assembly comprising one or more concentrated sources housing a respective concentrate solution and configured to prepare a mixed solution of an infusion fluid, wherein the water inlet duct is configured to provide water to the infusion preparation assembly for preparing said mixed solution of infusion fluid.