Dosing system for the dust-free dosing of powdered activated carbon (PAC) to eliminate all organic impurities from drinking- or waste water. Dosing directly from Big-Bag or silo by a dosing screw. The unit produces a suspension that is either conveyed directly to the filter or bassin a at a low back pressure or to a buffer tank from where the suspension is dosed. The level of the buffer tank is controlled automatically.