I used Red Star Cuvee yeast in my 3 gallons of cider, and when I stir it, I can hear it fermenting. It smells just fine, too. But my concern is that the fermentation isn't enough to activate my air lock. On the one hand, I'm fermenting in a five gallon bucket and all the yeast has to eat is the sugar from the apples, along with the brown sugar I added. On the other hand, it's been 12 days. Is my fermentation stuck, and if it isn't, how much longer should I ferment it?