I brewed 10 gallons of the big brew Hefe. Since my fermentation fridge only holds 1 carboy, I have one carboy under temp control and one just sitting next to it in the basement.
As of this morning both were fermenting very nicely, but you can see the difference between the 2.
The one not in the fridge is fermenting between 70-72 degrees. My basement is only about 64 degrees, but the fermentation is intense and I guess it is raising the temperature. The Krausen has exploded and the blow off tube is in full effect. The blow off bucket has an intense about of bubbling going through it.
The carboy under temp control is also going very well. But the fermentation is quieter. The krausen is about an inch thick. It is fluffy white and still an inch or so away from the blow off tube. The bubbling in the blow off bucket is steady ticking, but not to violent.
It will be interesting to taste the difference between the two at the June Meeting.