To work efficiently, flotation cells depend on continuous froth formation. If the froth layer is too thin, it cannot transport the sufficient amount of dispersed or suspended particles to the surface. On the other hand, froth that is too thick indicates that the reaction time of the chemicals is too long. This has the consequence that too little of the medium gets processed. A density-compensated level measurement is the reliable solution in this process: this ensures that the density of the liquid remains constant and optimizes the process yields over a long period.