@BMbikerider wow 20 yrs of consistency is great. I'm finding replenishment is certainly a pain. The odd variable in the equation is I'm finding it hard to know how much to replenish. Kodak's Z manuals lists Portra VC / NC but not the current gen nor Ektar. I think I'll try switching to premixed developer next time. Are you going so far as to use control strips to test variability? Are you guys storing the developer or other chems in the fridge? Are you storing bleach in closed containers with air on top to keep regenerated? Is my plan to use inert gas for the rest of my 5L going to kill my developer?