So the high pressure side doesn't peg right away, but the low pressure side does? That is weird.
I was looking for a leak since the gauge would rise even with both valves closed., I thought the cylinder valve was leaking...I'm confused by the note about soap testing when you pull the reg off and there is no leak. With the reg off the tank and no soap bubbles? That would seem normal with no gas pressure there??? Sorry, I'm confused, there.
The tank was freshly hydro'd and refilled thoughtank dump..... needs a refill