I wonder why mine turns lavender before I use it. My fixer also picks up a lavender hue. Do you think it could be my soft water? No...the fixer is mixed with distilled...though the developer and stop that precede it aren't.
Try mixing the developer with distilled water and see what happens.
Although it's safe to assume that Ian tells important facts concerning the discoloration - he knows his chemistry, for sure. It may simply be that some of the developer components have gone bad.
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