So I use a hop spider and hop sack and I have been removing my bag at the end of the boil. I have been looking at an IPA recipe that has hop additions at whirlpool 180 degrees. So I assume that means, add the hops when your wort reaches 180 degrees during the cool down. So for me, that begs the question, when are you supposed to remove the hop sack? Does everyone leave it in till transferring to the fermenter?