I have a remote cabin on a rain collection system with a 500 gal. holding tank which is hooked up to a water pump with a small 5 gal. pressure tank. The pump went out and I replaced it but it wouldn't hold pressure. The pressure drops and the pump comes on about every 30 seconds, even when there is no water running. I have now replaced the pump, pressure tank, pressure switch, and pressure gauge. I have looked over the entire system for leaks and found none. Any suggestions?

I have a remote cabin on a rain collection system with a 500 gal. holding tank which is hooked up to a water pump with a small 5 gal. pressure tank. The pump went out and I replaced it but it wouldn't hold pressure. The pressure drops and the pump comes on about every 30 seconds, even when there is no water running. I have now replaced the pump, pressure tank, pressure switch, and pressure gauge. I have looked over the entire system for leaks and found none. Any suggestions?

But have you replaced the check valve? Regards, tom