I am processing 4x5 sheets in a Jobo Expert Drum using Kodak C-41 and the minimum chemistry (210ml) for the drum one-shot. Getting stains and streaks that are sometimes visible in the film, sometimes not. The drums are not leaking. (that had been a problem once with E-6) I am using a wash between all of the steps. Using the recommended rotation speed for these drums and temperature. Attached is a section of a film. The stains are in the direction of rotation. I am using a pre-heat and a pre-rinse. i do not think I had the problem on previous batches but since they are not all scanned, it is possible that I missed seeing this. Only have two ideas. One is to increase the speed which I do not think will help. The other is use more chemistry. Hate to do this since Kodak is making this stuff very hard to get and very expensive. As in I had the fixer back ordered for nearly three months with Calumet and when it came the bottles were 5L rather than 10L and 30% more per bottle. Any ideas would be appreciated.

Chuck