A big beer with a crazy yeast and/or high temps and yes, big blowoff.
These were pitched yesterday around noon. The lager at the top was 5 gallons plus, 1.042 with WY2112. The other is a 1.062 IPA that came out just shy of 5 gallons, with WY1728. Temp is 55°. They appear to be reaching high krausen. Normally for me I get a little krausen on the lid, and on occasion about 10-30 ml in the tube.
I'll be adding a 60/- next week. If I move the keg out I can fit 4 buckets at a time.
Many feel that you should tape the temp probe to the fermentor covered with an insulator to get true fermentation temp. I don't argue that, but if you're running different beers at different stages of fermentation, IMO fermentation chamber ambient temp is just fine.
Sometimes I'll brew 3 in one day, when the last one is within 2°p of FG, I'll ramp up the temp. I'll do that plan if it's going to be a while before my next brew day. But I prefer brewing once a week and just keep it at 55° all the time. Not much difference in the final product.