I would like to connect a water timer to my rain barrel, but I cant seem to find a conclusive answer as to how much water pressure is needed to operate a timer. I have a 300 gallon water tank elevated approximately 3 feet. Adn will be running drip irrigation about 75 with 10 feeders coming off the main line. Do they make water timers that dont need 50 psi to work? If so, can anyone reccommend one?

Thanks very much for any comments.