Rapid completion of fermentation

[tonyole]

Hi guys. Very quick question.
Brewed a partial mash kit (Hefe) Saturday night. OG 1.043.
1500ml starter of Wyeast 3068.
Pitched at just below 80F but straight into a circulating water bath at 63F.
Blowoff tube. Slight blowoff during the next day.
Just removed blowoff tube and checked gravity tonight (3 days later) and the FG calculated to 1.005.

Could this be possible? Feel free to doubt the accuracy of my methods. Both gravitates were from a refractometer but the FG of 1.005 was calculated from the 1.020 reading.

I appreciate you guys. Awesome resource.

 

[chickypad]

Low gravity beer, good sized starter, relatively high pitch temp - yeah I think it could easily be done. If you're worried about the corrected refractometer reading check again in 2-3 days, should be stable regardless of whether the correction is on or not.

 

[tonyole]

Thanks. For a follow up question.....
Assuming it is at FG, is there any reason why I should leave the beer on the yeast for a while or should it head to kegging?

 

[dmarc85]

I would let the yeast clean up your beer at 63F for another 4-5 days minimum. After that, cold-crash it for 5 more days THEN go to kegging. A yeast cake is not going to hurt your beer at all in 2 weeks time. Cold-crashing before kegging will drop most sediment to the bottom of you fermenter, which will allow you to get the cleanest beer possible in your keg. Your rapid fermentation is typical for a beer with low OG and a large starter.

 

[chickypad]

For a hefe I'd just give it a few days to a week to clean up then keg it.

 

[tonyole]

Thanks all