Fishkeeping - is my co2 tank full?

"Exoir" wrote in message ...
I had my 2.5lb tank filled at a paint gun store.
Its at 1250psi Is this full?
At what psi will I need to refill it?

You can not know if it is full without weighing the tank and subtracting its empty weight. The CO2 in the tank is mostly liquid with
some gaz on top at 800psi (at room temperature). There must be some other gas mixed with the CO2 right now that contribute to the
excess pressure and will be evacuated in a few days of use. The pressure will thus gradually drop to 800psi and not budge from there
until all the liquid CO2 has been used up. When the pressure starts to drop below this level (about 800psi), then it is time to
refill the tank.