No krausen in the carboy but have it in the hyrdo sample tube?

[Hermit]

Second batch in a row. Using the 'old' Notty. After shaking the carboy some I draw the sample and put it aside. The tube is open to the air and the carboy is lightly covered with foil. The carboy is a five gallon with 3.5 gallons of beer so there is enough head space and air that I don't think this should make a difference. If both had no krausen I wouldn't be as puzzled. The temp in the fermentation chamber is only slightly lower. About 68F in the basement naturally and I have the fridge at about 65F. The carboy is churning away just fine. Thoughts?

 

[david_42]

I see this consistently, the sample tube almost always has a higher krausen. May be nothing more than the tube, being narrower, has less air circulation so the bubbles last longer.