Hello, Steve Anchell's book mentioned the capacity of TF-3 fixer is 20 8x10" prints or films per liter. Excuse my English & Chemistry, but 1. Is the mentioned capacity meant to be for stock or 1:4 dilution? 2. Can unexhausted working solution (1:4 dilution) be kept for use another day? 3. If I were to mix 800ml of 60% Ammonium Thiosulfate from scratch, how much of Ammonium Chloride & Sodium Thiosulfate do I need? Many Thanks!