I would like to pump from a very small stream for use to water trees and bushes. I plan to install a pump relay to control when the pump is running but also want to make it so the pump can be started in the house and then go to one of several faucets (large yard) to turn on the faucet. I am thinking a pressure switch would shut off the pump when the faucets are closed but allow someone to go to a faucet and get water. Do I need a tank? Would a flow switch be a better choice? A pressure switch set near the cutoff pressure of the pump without a tank seems like it should work for all but very low flows. Want to make this reasonably easy to operate by others. Since the stream is small and sometimes stops toward the end of summer I also planned to monitor motor current and shut off when prime is lost. Could use a float switch but there is extra wiring and complications - distance between pickup, pump and end use and stream has high flows at times that could take out the float switch.