Hi, pretty simple question and I'm sure I could find the answer but figured I'd just as. I just bought this powder kit to develop some 120 film in my Paterson tank. The tank I use is the one that does 2 rolls of 135 or 1 roll of 120. When doing BW I mix up 500ml (50:1 rodinal) solution, I'm thinking since this is the one liter kit I can effectively mix 500ml now, use it till its exhausted, and then mix the remaining solution for another 500ml. I am assuming I should get more rolls out of the kit doing this? Is it worth it or should I just mix it all at once?