Originally Posted by Epimetheus
Thanks for the info. I'm a newbie and thought it was necessary to have a vigorous boil the whole time. Do you get an effective hot break if you get it boiling but not a real rolling boil?
No, not really.
You need to watch it like a hawk until after the hot break, plus using Fermcap helps. After the hotbreak it won't boil over.
But I've boiled over a 5 gallon batch in a keg, so it's definitely possible! I turned my back for a minute, and over it went.
After the hot break, you can back it down a bit as long as it's still a rolling boil.