If you are using 50 GPM, a 3,000 gallon storage tank won't last 6 minutes. If the well will make 150 GPM, you don't need a storage tank. You just need a pump system in the well that will produce any amount of water you want at 50 PSI. If the pumping level is about 250', you need a 50 GPM, 7.5 HP pump. With and 80 gallon pressre tank and a CSV3B2T Cycle Stop Valve, you could use from anywhere from 5 to 50 GPM at 50 PSI constant.