My houseboat has a plastic black water tank. The boat is a pontoon style. The holding tank is mounted under the main floor deck, but above the lake water. I want to add tank monitor and am considering the externally mounted type of sensor that uses foil strips to read the tank level. (I am looking at the SCAD 10018 model). My question is: Does anyone know if these sensors can be installed in this environment - exposed to weather, etc. where they will get wet at times?