I was just wondering, could I use a carbonation cap (air line ball lock to PET screw cap adapter) or even just a sandstone to oxygenate some small bottles of water so I can prepare several ahead of time and just dump one bottle into 5 gal of wort? I don't have an oxygen tank and haven't done the math to see if you could absorb enough oxygen into a small enough volume of water. Potential benefits I could see would be extreme convenience at pitching time and keeping the sandstone clean because it only touches water not wort.