For a pressure tank with a 40 to 60 psi pressure switch, the best setting for the tank is typically 2 psi below the cut-in pressure (the lower number). So in your case, with a 40/60 psi switch, you should set your tank to 38 psi. This ensures that the pump operates efficiently and maintains proper water pressure throughout your system. It’s always good to consult your pressure tank’s manual or a professional if you’re unsure about making adjustments