Hi Max,
I have now decided to use mercury switches on the outside of the switch setup I have made up. Only problem with mercury switches the wires have to move as the switch rocks so this means because these single insulated wires are exposed in the tank I will have to drop the voltage to these switches down to 12 volt and that means I will have to use a 12/240 relay and also add a 12 volt power supply. Only way I can see of making it safe and reliable
