Hey guys. I have an odd question and I'm not sure of the best place to put it. Anyways, I removed the airlock on a 3 gallon carboy that is at 70 or 72 degrees. I blanketed the mead with CO2 at about 50 degrees and replaced the airlock. It apparently created a vacuum, which seems odd to me given that the gas should be expanding and pushing out of the airlock. Does anyone have an explanation for this, and perhaps even some advice as to how I should proceed?