Hello. I’m posting because I’ve been searching the forums and not quite getting the info I’m looking for. I’m currently in primary fermentation of my first wine; a Malbec from 6 gallons of fresh juice. Upon searching the net for wine making info one thing is clear: absolute minimal headspace in during secondary and subsequent aging. That is assuming that my transfer fits perfectly into one of my 5, or 6.5, gallon carboys. I do not want to top off with another wine and dilute this batch. The question that brought me here is what are your thoughts on topping off the carboy headspace by purging with food grade CO2 regardless of actual space? I’m asking to generate discussion here and see how others react. Applying what I’ve read here and elsewhere, and applying 10+ years of home-brewing experience, it would seem to be the the wine would be fine. The CO2 will purge the oxygen from the carboy. I figure (and this is where I’m looking to experienced vintners) natural degassing will push excess CO2 out of the airlock, rather than absorbing (like long term aging beer).