Copied and pasted from Homebrew42, on Beeradvocate.com... just for your consideration:
"Whirlfloc was not developed with homerbewers in mind, it was developed specifically for commercial brewers. When the manufacturer of whirlfloc found out that it was being marketed to homebrewers he was shocked. The interesting thing is that when it's repackaged for sale to homebrewers it's always labeled with something like "Use one tablet for 5 gallons of wort. Add 15 minutes before the end of the boil", but this is not at all what the manufacturers recommendations are.
I've seen the manufacturers specification sheet and according to them the correct dose is one tablet for something like 12.5 gallons of wort, and the tablet should not be boiled for more than 5 min. According to them, the longer you boil the tablet, the less effective it becomes. In fact the reason it's called "whirlfloc" is because it's supposed to be added during the whirlpool."
Seen this before. I only add a half-tablet, at the 5-minute mark.
Quote from: "Richard"Seen this before. I only add a half-tablet, at the 5-minute mark.
I only add 1/2 a tablet, but do so for 15 minutes. That I'll change to 5 from now on. Good find, thanks. I'll post this around.
Mmm... I too had read about the 1/2 tablet various times before, but this whole 5-minute thing is new to me.
Probably not a HUGE deal (my beers have been pretty clear lately), but I'll be curious to see if I (or anyone else) notices a difference.
I've tried 1/2 tab with some (like more than 65% wheat) beers, and it is not sufficient, but otherwise it works well. I've always done the 15 minute mark, but I'll have to see about the 5min addition. Hmm.
News to me too... I guess its a 1/2 tablet at 5 minutes next batch and see how that goes.