Fermenting in Sanke and storage
 

I have a Sanke sitting around and needs a purpose. I am thinking about doing a 12-gallon or so batch, and using the Sanke for fermenting (This should be a good headspace/volume IMHO).

My thought though, is that I want to transfer (can do under pressure) from the Sanke in sections. Meaning, after fermentation is complete, I want to transfer 5-gallons to a serving corney. Which will leave 7-gallons remaining in the sanke.

It may be another month before I refill the corney with this brew.

If I keep oxygen out of he sanke as best as I can..can I get another month of leaving it in the sanke until I transfer to my serving corney with that headspace?

I assume you want to do this because you only have one corny keg? It would probably be all right as long as you transfer it using CO2 and then blanket the remaining beer with some CO2. The other way you could do it is force carb your first keg and transfer it into bottles. Then fill the keg again with the rest of the beer. That way you don't have to worry about beer sitting in the primary for potentially months.

If you're transferring under pressure, you're not risking oxidation -- you're adding CO2 to the fermenter to do the pushing, not O2.

That said, even with the price of corny kegs, why not just pick up a second corny and fill them both? I do 10.5 gallon batches so I can fill two cornies, and that way it frees up my fermenter for the next batch...

I just placed an order today for 4-more corny's (that should do the trick!).... I wanted to hear other's logic before I tested a batch. The sankes have a future home when I will expand into a 3-vessel brewing system.

You are going to love fermenting in Sankes!! My one tip for you is to build some sort of keg washer. Mine is just a bucket, pond pump, and a capped and drilled sprinkler riser. Works really well though for cleaning.

I ferment in a 1/4bbl and I love. No light gets through, the bottom is sloped to get the most beer out when racking, and if I need to move it it's much easier to move than a carboy.
To clean I hit it with the garden hose first, dump it. Fill with chlorine/hot water solution and let it sit over night and rinse. Always comes out clean.

Does anyone ferment and carbonate in a sanke, then push to a corny to serve?

I don't think that would work. You would want to rack the beer of the yeast before carbonation. Why would you want to carbonate in a sanke vs. a corny keg?

No real reason for doing so, I ferment in sankes And was thinking about those who use co2 to push the beer out after fermentation, just curious if you could carbonate in there before pushing to a corny for serving.

Yes. See the closed pressurized fermentation thread, or the wiki: http://www.homebrewtalk.com/wiki/index.php/Closed-system_pressurized_fermentation. I ferment in corneys and ramp up the pressure at the end of fermentation.