I just brewed my first extract kit this past weekend. I have one 6.5 gal glass carboy and four 5 gal carboys. While my 6.5 is in use for two weeks, I thought about brewing another extract kit. Should I split it into two 2.5 batches and use two 5 gal carboys or keep them in one? I anticipate a loss of wort if I put the full 5 gal in a 5 gal carboy instead of 6.5. Is there too much headroom in the carboy to just have 2.5 gal of wort in a 5 gal glass carboy? Thanks!