What psi in full 10lb CO2 tank?

Phantom Phish · 05-10-2003, 01:42 PM

I'm setting up a brand new Calcium reactor. I have a new 10lb CO2 tank that I got from Premium Aquatics, and dual gauge regulator from Andy. The tank is samped "3Al 1800", which I assumed means the tank is rated for up to 1800 psi. I had the bottle filled locally, and when I attached the regulator it reads the tank pressure as 900 psi. My question is, did I get a short fill from the folks who filled my tank, or am I reading the stamped markings on the tank wrong? Any body out there using a 10 lb bottle, what psi do you get when you fill your tank?
Thanks for any help.

ckreef · 05-11-2003, 02:20 PM

The tank is probably rated for 1800 psi ---- BUT ----

CO2 is filled as a liquid and by should be filled by weight not volume.

Scuba tanks are filled by volume and should reach the expected psi. CO2 like propane is filled by weight and my 5 lb was only filled to 800 psi similar to your 10 lb.

As you use the CO2 gas (floating above the liquid) more of the liquid will turn to gas and your filled psi will not change much until you are almost empty --- at which time there is no more liquid to turn into a gas and you run out.

Did any of that make sense????

Charles

Phantom Phish · 05-11-2003, 05:13 PM

Charles:
That makes perfect sense!
I didn't realize the CO2 was in a liquid state. I was assuming it was all gas, and expecting it to act like my scuba tank, as you mentioned.

I should have figured out it was liquid when they gave me the tank back and it was ice cold with condensation on the outside.

Thanks for clearing that up for me!
Chris