Just an update on the float switch, it failed again even though the switch is above the water level. All I can put it down to is poor quality reed switches in them. Problem is there is nothing else available so my only option is to some how set it up with a mercury switch because everything else relies on Chinese reed switches. The main issue I have using mercury switches is getting it 100% sealed up because it will have to be set up in the water. What I can't believe is that I am not the first person ever in this world to want to pump water from an underground tank into an above ground tank, it has been done before