Been using the little red bottles to add oxygen prior to pitching yeast for a while now; can get about 3 batches out of each one. They're about $16 a pop at the local hardware store, getting pricey. So I'm looking into buying a 20cf tank I can exchange at the gas place. What regulator works with one of those for brewing? What tubing to use? I have carb stones (don't remember the specific micron at this time) so I'm good there. Thanks in advance.