Interesting scenario. I have a 10 gallon all grain batch of Heffeweizen, split into 2 glass carboys. 1st generation Harvested yeast from a previous 10 gallon batch, (wyeast 3068)- pitched @ 9:30 PM after a 2 day double starter and fermentation began within 1/2 hour. Went great all night; @ 5 AM both carboys had healthy krausen and Co2 blowoff. At 3:30 pm, (18 hours after pitching) carboy two still has krausen, but carboy one is without krausen. CB #1 is still VERY active...you can see the yeast bouncing all over the surface of the wort and Co2 is being produced, just no remaining krausen.
Same batch of wort, same yeast (divided in half just before pitching)--I've never seen such different results.
Should I have any concerns that there is no Krausen-ing in CB #1?
Wort Temp is about 71.5 degrees.
thanks for comments