I just had to chime in. Though I do not doubt the veracity of Dan's experiences, I have never had Xtol failure. I use the five liter packs diluted with filtered tap water, stored in a tank with a floating lid. I develop 1:1 in a Jobo processor. the films I consistently develop are Ilford films mostly. About the closest thing I had to failure was when I ran some tmax 100 for the first time using Kodaks reccomended time and ended up with extremely thin negatives. I did a second run, virtually doubling the processing time and the negatives came out fine, but it did give me pause. thankfully TMX is not a film I, or my clients use. a couple hundred rolls in Xtol so far and no failure yet. Knock on wood.(posted 8418 days ago)