It's time to change my resin in my twin DI setup (suddenly shot up from 10/12ppm to 22ppm!). So, I changed the resin in vessel no. 1(the 'older' of the two) and swapped to make make it 'no. 1). Vessel no. 1 now has a reading of 13ppm and no. 2 is 000ppm. But it's still coming out of my pole end 22ppm(even after running it for a minute or so and giving them a good shake!). So would this just be 'old' water not flushed through the hose reel/pipes etc, or what have I done wrong? Arggggghhh!!