Regulator reads zero but still some gas?

[zombie2k]

Some may remember the problems I've been having with my regulator pressure dropping drastically and unexpectedly. So the pressure guage has been at 0 for about a week or so now....and it's still pumping gas out just fine!

Is it possible there is still gas in there (the cylinder) or is it just broken (and thats the answer to all my questions)?

 

[jim692]

Which pressure gauge is reading 0? The one on the inlet side (co2 tank side) of the regulator or the one on the outlet side (fish tank side) ?
As a general rule most gauges are only accurate to 5% of their face value and 1/2 their total rating. Eg. a 2500 psi compressed gas cylinder gauge would be most accurate at the 1250 psi range and then only +/- 125 psi.
The same gauge wouldn't read well at say 100-400 psi. And if it read 0 you still may have 125 psi or more in the tank.