A paper sizing composition is provided, which comprises a water-soluble salt of Ca and at least one organic acid; and starch. In contrast to the conventional cleaning solutions based on fluoride chemistries, the present invention can significantly reduce the oxide loss resulting from the exfoliation, while still providing an excellent cleaning efficiency. At least one roller displacement unit, which enables both shaft sections to be displaced in an axial manner in relation to each other, is also provided. The receptacle is pivotally mounted for movement with respect to the distributor, and is self-leveling such that liquid is divided by the receptacle outlets into predetermined proportions. In the event it is established that a developer station was not needed or will not be needed, the developer station is shifted into a standby state in which at least one part of mechanical actuators of the developer station is stopped.