So I went to the brew store tonight and while I was there spotted some glass carboys on sale. I bought 2 not not realizing that the mouth is a different size than my better bottles that I normally ferment in. I was planning on moving 10 gallons of cream ale into the new carboys tomorrow, as I am leaving for vacation on Sunday (2 days from now) and don't want them to sit in primary any longer. Any ideas on a makeshift airlock whilst I'm gone? The brewstore is an hour away and I really don't want to make a trip tomorrow. I was thinking a sanitized balloon would work since very little co2 is being produced. Thanks for any and all suggestions!