EDIT: AW CRAP! I see this has been answered before. First post and I just post an overasked question. My bad. Mods, feel free to delete this turd. I'm a cheap bastard and have 100+ rolls of BW film sitting in a big box so I figured rather than buy 1 gallong bags of D76, I'd buy a 10 gallon bag. But then it arrived (actually Legacy Pro L76) and suddenly I've got cold feet. My plan was to just use 10% of the bag at a time, but my concern is that I'll pour in an unbalanced mix of powered chemicals. I'm assuming that there are actually a number of different powered chemicals in the bag, and instead of having a mix of 50-50 (say if there were only 2 chemicals) I'll end up with a mix of 30-70 or something awful like that and end up with a useless batch off D76. So, can I mix just 10% of the bag at a time or would that ensure a disaster? Thanks.