Next weekend I plan to brew my fourth batch, Caribou Slobber. I purchased yeast nutrients (LD Carlson urea and diammonium phosphate) and an extra yeast packet. With the previous batches I was concerned that I couldnt get all the way down to the target FG, so for batch #3 I rehydrated one package of yeast, then at the last second decided to sprinkle another yeast packet on top before putting on the airlock. The beer was fine. My questions are: Which would be the most beneficial, adding the yeast nutrient or adding a second yeast package? I know that you can make great beer without doing either, but if I add both, I am concerned about getting too vigorous a fermentation, needing my blow-off tube. I want the beer to fully attenuate. I am sure neither alone could hurt the process. Second question is in regards to when to add the yeast nutrient. I have read on posts that they added the nutrient when there is ten minutes left in the boil. Is this the ideal time to add? Also there seemed to be no set amount of nutrient that is universal. The package says to add 1 TSP PER GALLON MUST, which doesn't make sense to me. Must? I didnt read anyones post that said he/she added 1 teaspoon per gallon of wort.