Boy, am I learning that every brew day is different and throws up it's own curious array of gotchas. I don't use a hop sock, and always whirlpool the chilled wort before transferring to the fermenter. For a 5g batch, my KFL has averaged about 2L, even when using up to 3oz of hop pellets. There is usually a tidy pile of trub in the center of the kettle.
With my latest batch, using nearly 4oz of hop pellets, I ended up with about 4.5L of trub, which was a wort/hop sludge evenly covering the bottom of the kettle. Half the hops were a new variety (Styrian Golding). I'm not sure if they were processed differently or what. So that was interesting, and I can only think that next time I'll use a hop sock and hopefully this will reduce some of the sludge.
Not wanting to lose all this wort, I decanted into two x 2L bottles, and let it settle for about 5 hours. I was able to decant about 1.5L of clear wort from this, boil it, cool it, and added to the now actively fermenting wort (7 hours after pitching). Is this a frowned upon practice in terms of how it might affect the ferment?
As an aside, I overshot the ferm temp: 74F instead of 68F. The subsequent blowup took me over an hour to clean up. Argh!
Something else I learned this time around is the effect of cold temperatures on propane tank performance. With ambient hovering around 0C, my boil gradually diminished over time until it was hardly a boil at all. With 10 minutes to go, I remembered I had a spare tank, so swapped out the one with nearly a centimeter of frosting on it. The improvement in boil vigor was remarkable, and I regret that I didn't think of it sooner.
That was my last brew day for 2014. I need a rest now
Cheers,
BDP