I don't know what you mean by 'commissioned for the first time'.
You have not given enough information for me to understand what you want done different.
Are the three 'buttons' actually water level sensors? If so I can understand why you want the pump to start wen the tank is empty (all three level sensors LOW) and stop when the tank is full (all three level sensors HIGH). It also makes some sense that once the pump has started you want the pump to continue to run after a power failure, even if the tank is partly full. I don't understand what else you want that is different.