I have used all sorts of chem storage strategies and an absolutely full glass container seems to be foolproof for stock D-76. But of course I don't always have a full container and enough marbles to take up the slack just doesn't interest me. (what do you do with all those contaminated marbles when not using them?). So when someone on that other forum mentioned using Propane to displace the air in a part filled container it got me interested, but.... Is it a good idea? Propane will displace the oxygen but will it contaminate the developer, fix, toner etc. Supposedly this is a poor mans copy of a product sold for this purpose by tetanol (sp?). Is this more internet folklore or an actual good working solution? No pun intended.