Filling a carboy to the bung?

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Arctic Contributor
Oct 26, 2008
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Lately I have seen several pictures in here of carboys with airlocks and the wine is no wheres near the bottom of the bung. So, just how critical is it for the wine to be to the bottom of the bung. How much headspace is too much?
I dont let it go beyond 3" below thw bung without topping up, displacing or filling with C02!
3" seems like alot, but there is that much tolerance, huh?
If the wine is still/stabilized I try to get it 1" to 2" inch from the bung. 3" isn't really gonna hurt anything though as it is up in the neck and the surface area, which is more important than volume of O2 in the carboy is minimal.
Maybe I didn't phrase this right. the pictures I am refering to are not in the neck at all, but a couple inches below. I can understand some a little from the top of the carboy, I was curious about some that are "far" below the begining of the neck. One in particular I seen was a photo in WhineMaker's album, seemed pretty low. Was really wondering if that much headspace was "tolerable"
If it was aging then it might be of concern but it could bvery well be still fermenting and at that point is no concern at all!
Gotcha, some people ferment in a carboy, though I have been convinced by everyone in here to ferment in a bucket, so it very well may have been in the primary. So when aging, try to get it at least to the begining of the neck?
I do kits in a bucket but I do most other wines in a carboy. I normally make a country wine to 5 gallons. I will ferment it in a 6 gallon or my on 6.5 gallon carboy.
I have... at last count.. 18 x glass, 1 gallon carboys. Used for fermenting, ( secondary) and aging in bulk.

Primary ferment, up to 5 days done in a plastic bucket.

I do all my fermenting in buckets. My country wines usually require this because I use a lot of fruit, I really need to get a 10 gallon fermenting bucket or bigger!
The pictures you are reffering to are indeed still fermenting(secondary), although the primary fermentation was done in a bucket.. Most of the kit wines do not want you to top up until the clearing stage, at the end of fermentation.. At that point, all of mine have been up to the level of my Pinot..
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I should also add that having that extra headspace in the carboy before clearing and topping up has made it easier for me to degas. Lots of room for the foam, so I have avoided the dreaded foam volcano.. :)