Everyone should have a tank pressure gauge from McMaster-Carr:

3846K1 Multipurpose Gauge, Steel Case, 1-1/2" Dial, 1/8 NPT Bottom, 0-15 PSI at $10.70

Just JB Weld a YS brass nipple in the bottom. They claim it is calibrated to 2% at midrange which is 7.5 psi - perfect for us.



3/4 on the main needle ain't right and points to the regulator.