I've only had one film 'recirculate' and it was Konica IR750 which was in the tank with a roll of FP4 at the same time. The FP4 showed no affects, but the Konica had the very distinctive pattern. I have seen another example of Konica doing this, although much finer pattern than my example, so maybe if this is an effect your after, this would be a good film to experiment with. In my example, I believe my wash temp climbed to approx 40C after the 'mixer' tap was bumped. The devl, stop & fix steps were as the correct temps. I haven't tried to repeat this as I guess you need to plan your pictures to suit! Some of my images were of the Shrine (a stone building) here in Melbourne and I could see that the effect could probably be used to some use.(posted 8755 days ago)If you're after negs with big imperfections, maybe take to it while drying with a hair dryer... you could get crinkles, splotches and cracks I guess! I've never tried this I might add!