Pump cycles randomly and empty RO tank

[Cobra1365]

Hi folks,
Newbie here with some questions.

Recently, I noticed my shallow well Gould J5 pump would cycle with no demand. I checked all of the sources and did not see any nefarious leaks or anything running.
Additionally, my RO system pressure dropped off and yesterday actually quit. I checked that tank and it was empty.
I had previously isolated the RO system to see if it was causing the pump to cycle. Pump still came on.
I have not yet checked pressure tank on well pump.
I should also say that my system has a check valve just before pump inlet as well as foot valve. What are the odds both of them have a slow leak allowing pressure to drop off?

Pump was replaced last August (2018) and tank approx 3-4 yrs ago. RO is new as of Jan this year.

I plan to isolate the water supply to the house today. If pump still comes on, then it has to be bladder tank or check valves...right? But, why would the RO be empty? Do I have two coincidental issues?

BTW, normal tap water, shower, etc has full pressure, right away. No discernible drop while running. Though I did notice this AM, a knocking noise toward end of pump cycle after running kitchen faucet.

Any ideas are greatly appreciated.

Mike

 

[Valveman]

Pump coming on when no one is using water is going to be bad check valves. The only check you need is the foot valve, as the other one will keep the foot valve from having enough pressure to close properly. That knocking noise is probably your pump bouncing on and off, which isn't good. Replace the foot valve first, then see if you still have problem with the RO system.