I mix about every month and a half. I use a 6 inch plastic tube that is 2 feet tall. I float a tight fitting plastic lid on it and then put another lid over the top. I have never experienced the sudden death syndrom but I do find that not all films follow the extension guide line the same. I keep a running log on the wall of every film and temp and time and roll number. Then refer to that with every batch. I find that FP4 in particular gets reluctant to develop after awhile and I have to extend the times for it far more than for Kodak films. I am finding that ACROS also needs greater time extension than Kodak films as the developer exhausts. FP4 and ACROS print really nicely though regardless.
Originally Posted by PHOTOTONE