The flow rate can be set from 0 to 5 l/min in 0.1 l/min steps. A precise mass-flow meter is used. This measurement is independent of the pressure and temperature variation of the air.
Commonly used floating ball capillaries (rotameters) give inaccurate readings in this case. A proprietary proportional air valve adjusts the flow rate continuously.
A new self-cleaning elastic air micro-sparger has been developed. Its special construction allows an automatic elimination of salt deposits, which would block the airflow in normal spargers. This is important particularly for micro-spargers having very narrow channels.