So, I've been brewing all grain for about 2 years total. I had to take off for about 18 months due to a job transfer. (Moved into a rent house while building new, didn't want to set up brewery and have to tear it back down.) Anyway, I've made a total of 59 batches. The first 58 batches, I would throw in the Whirlfloc and immersion chiller and boil the last 15 minutes of my boil. Then chill the wort to fermentation temps, pull the chiller and swirl the wort and wait 10 - 15 minutes. All I would get would be a fluffy sediment in the bottom of my pot, suspended equally across the entire bottom of the pot, no cone at all. Recently I bought a new Therminator chiller and used it on my last batch this past Sunday. I had decided that I wasn't going to even try whirlpooling anymore, as I had no luck in the past, but I decided to try it one last time to see if wort temps had anything to do with it. I turned the fire off my brew pot at the end of the hour, gave the wort a good swirl and waited 10 minutes to start my transfer to the carboy. As my pot was draining and I began to get to the bottom, much to my surprise, there was an almost perfect cone right there in the center of my pot. It was almost like a miracle, I had to wipe a tear from my eye! Anyway, maybe I'm the last person in the hobby to know this, but I wanted to pass this along to anyone else that may have not known why whirlpooling didn't work for them. I'm not sure what the solution would be for those using immersion chillers, but there are much smarter people on here than I that could suggest solutions for that. Batch 59 - perfect cone! Oh, and by the way - the Therminator is almost magical. Hard to believe that you can drain 208 degree wort through that and it go into the carboy at a nice 66 degrees.