Level gauge system with wettable propagation device

A level gauge system for determining a filling level of a product contained in a tank, the level gauge system comprising:

• a transceiver for generating, transmitting and receiving electromagnetic signals;
• a signal propagating device connected to said transceiver, said signal propagating device comprising a signal directing portion arranged and configured to direct a transmitted electromagnetic signal along a generally vertical path towards a surface of said product inside the tank, and to return a surface echo signal resulting from reflection of the transmitted electromagnetic signal at said surface of the product contained in the tank;
• and
• processing circuitry connected to said transceiver and configured to determine said filling level based on said surface echo signal,
• wherein a surface of said signal directing portion comprises a surface portion that exhibits a wettability defined by a contact angle between said surface portion and water being less than 30°.