Blow-over

So we brewed up a good looking batch on Sunday, and got everything set. Transferred it into a carboy, pitched yeast and set up to do it's thing. We ran a hose from the top of the carboy to a water filled bin to take any blow off that occurred. One time before we just put a little bubbler on top and let it run, and I have never seen such a mess...This time, about 2 hours after pitching, it was beginning to bubble. Temps were hanging right around 65 degrees, and pretty steady. Blocked off the lights to the area and went to bed. After work the next day I stopped in to make sure things were still good, and saw that there was a pretty good amount of blow off.

My question is:
How much is normal? This time seemed like a pretty large quantity blew out, and I wasn't sure what the norm was, or if there was something we should be doing instead to prevent it. Thanks for any thoughts, and everyone have a great rest of their day.

It totally depends on the beer and the yeast. I wouldn't worry about it at all!

Also, blowoff could appear to be random, for instance one beer will blowoff one time and not the next. It depends on a variety of different criteria that are usually different from one brew to the next, for instance a one degree difference in temperature or one point difference in SG may be all it needs to blowoff or not. The yeast are the masters here, we have no control and there is not a normal or abnormal amount of blowoff.

Keep on brewing my friends

Well, that's good to hear. I hadn't had one blow over so vigorously or so quickly before. I've run into really slow fermenters and some that seemed to go on forever, but never that fast. I was a little worried...But at least this time it went into a bin and not all over the floor...