Hello All, This morning I mixed up a litre of Kodak RA4 Blix and put it into two 500ml pop bottles. A few hours later, after working in the darkroom, I wanted to replenish my Blix with what I made up earlier. However, the Blix had gone a muddy light brown - just like the colour of engine oil if you get water in it. It was jet black when I mixed it up. Any idea what's going on? Thanks!