The present invention relates to methods for dosing a substituate produced by a blood treatment apparatus. Dosing for the present invention is via a hydraulic system of the blood treatment apparatus, the hydraulic system having at least one dialysis liquid supply line which leads into a dialyzer and at least one substituate line. Regulating or controlling the size of the share which passes through the second filtration stage is performed by affecting at least one conveying apparatus and/or at least one flow limitation device and/or a flow divider valve, which are each located or which each operate in the dialysis liquid supply line and/or the substituate line and/or in the branch line which connects the dialysis liquid supply line with the substituate line. The present invention further relates to a control device, a blood treatment apparatus, a medical functional apparatus, and a computer-readable storage medium related to the methods.