Near Empty CO2 Tank - Gauge In Red Zone

My 10 gallon CO2 tank is near empty, the pressure gauge seems to be dropping faster in the RED zone over the past few days.

Will the pressure in the tank change enough to move the gauge as the tank nears empty? I have read that the high-pressure gauge isn't worth a whole lot but I am confused as to why it is now dropping faster when in the red zone.

Has anyone else seen this?

The CO2 in the tank is liquid and slowly "boils" away as it is used. So normally the pressure is a function of the temperature - until the very end. Once all the liquid is turned to vapor the pressure will drop very fast. Time to refill.

When I brought my first bottle home it read almost 1000 psi - then I put it in the fridge with the keg. In the morning the pressure was on the edge of the red - took me a while to realize what had happened.

The high pressure gauge on a CO2 tank is not the best indicator of its contents. The CO2 in the tank is a liquid under pressure and the gauge reading is of the vapor on top of that liquid. That pressure remains almost the same until the tank is virtually empty then drops quickly, which is where yours is at now.