Depends. If you drew 4 gallons, that would correspond about a 15 gallon pressure tank. If your tank is 30 gallons, then it might benefit from topping off the air pressure (on empty tank) to 40 PSI). You could consider a bigger tank. How long does the pump run each time?
You could also consider a pressure switch with a wider range... maybe 35 to 65 or 30 to 60.