How long will my gas tank last? Dear All, I've a question for you that's driving me a little bit crazy. I'm trying to set up low oxygen tension cell culture chambers to grow my cells. Here is a picture: The chamber is cylindrical shape and has a volume of 1.2 liters, it's at room temperature and room air. I purchased a 50 liters tank at 150 bar of 2% oxigen, 5% CO2 and 93% N2. My protocols says to connect the tank with a 1/4 inches tube to the chamber and let the gas flow through the chamber at 2 psi for 2 minutes. Then I seal the two holes of the chamber and the air mix inside will be 2% O2, 5% CO2 and 93% N2. I know the protocol is correct, so I don't care to reduce the flow time. I'm just wondering how many chambers I can prepare with a 50 liters, 150 bar tank. Of course I'm looking for an approximate solution of my problem...it's just for cost estimation. Thanks!