Abstract: A system (1) and method for coating seeds with a treatment liquid, in which transfers of seeds and liquid within the system arc controlled by a control assembly (6) in accordance with selectable operational modes. Some modes involve determining an actual amount of a quantity and/or a subquantity of seeds transferred from a bin (24) based on a change in the weight of seeds remaining in the bin (24), and adjusting the system (1) to account for a difference between the actual and expected amounts. Other modes involve determining an actual amount of a quantity and/or a flowrate of liquid transferred from a tank (750) based on a change in the weight of liquid remaining in the tank (750), and adjusting the system (1) to account for a difference between the actual and expected amounts. Further, these modes can be performed together for even greater redundancy and accuracy.