The method involves proving at least one dialyzing liquid concentrate in at least one accommodation unit and water to dilute the concentrate, mixing concentrate and water in a defined volume ratio and feeding the resulting dialyzing liquid to the dialyzer at a defined rate during a defined treatment period. The rate can be adjusted so that a defined residual quantity of concentrate or none remains in the accommodation unit at the end of treatment. The method involves proving at least one dialyzing liquid concentrate (K1,K2) in at least one accommodation unit (12,13), providing water (W) to dilute the concentrate, mixing concentrate and water in a defined volume ratio and feeding the resulting dialyzing liquid to the dialyzer (1) at a defined rate during a defined treatment period. The dialyzing liquid rate can be adjusted so that a defined residual quantity of concentrate or none remains in the accommodation unit at the end of treatment. AN Independent claim is also included for the following: (a) an arrangement for supplying the dialyzer of a dialysis device with dialyzing liquid.
