The last two batches of bleach for Kodak Sepia I made up, having sat unused in it's bottle for a couple of weeks, has changed from it's original yellow colour to a blue. Moreover it has stained the (translucent plastic) bottle blue as well. I threw the first one away and made the second, kept it in a new bottle, but it's done the same. Both worked fine the first (and only time) I used them.
My previous batch of bleach lasted me about six months, possibly longer, never anything but yellow in colour.
I cannot think of anything I've changed but something obviously has. Anyone have any ideas?