The present invention relates to a blood treatment apparatus: at least one first source for a saline solution, a fresh dialysate, or a substituate as a first fluid； at least one first conduit portion which connects to the first source； at least one second source of a second fluid in the form of a concentrate or a solution； at least one second conduit portion which connects to the second source； at least one third conduit portion, which is in fluid communication with a section of the extracorporeal blood circuit to which both the first conduit portion and the second conduit portion are fluidly connected such that both the first source and the second source are in fluid communication with the third conduit portion； a first fluid conveying device, arranged to convey a fluid present inside the third conduit portion. The invention further relates to a corresponding method.
