Stormin Mormon wrote:
Just for diagnostic, I'd also turn off the well pump
breaker, and put an air compressor on the tire valve.
Inflate to 30 PSI, See if you can get air to come out
the water faucets (sign of leaking diaphragm).

Who knows? Might just be the tank needs reinflating.

That test will tell nothing unless he runs the water dry after shutting off the
pump.