Originally Posted by Phunhog
From my experience you are exactly right!! Water does a much better job of regulating temperature swings than air does. I think most people do the temp controlled fridge because it is easier if it really hot or really humid. Where I live though the water bath works great because depending on the weather I might have to heat and/or cool the fermentation.
Yes, I've noticed the same thing. In my ale pail, in a cooler filled to the beer level with water, there is about a 1-2 degree difference between the beer in the center of the fermenter and the water bath.
I use an aquarium heater in the water bath in the winter, and frozen bottles of water in the summer, and float a thermometer in the water bath. The one difference with heating is that I don't circulate my water, so I keep the floating thermometer away from the heater so I can get an accurate reading and it works just fine.