Thanks for the reply. I guess I ought to have been a little more specific in my original post.
1. The first thing I tried when my iP6000D stopped printing magenta and more specifically photo-magenta, was to print a nozzle check and run the nozzle cleaning utility.
2. After 3 or 4 attempts...
My iP6000D has stopped printing photo-magenta altogether and magenta is streaked. I assumed the print head needed cleaning, so used the saucer of water/alcohol and tissue paper trick to take care of it. I was a bit surprised to notice as soon as I pushed the print head into the wet tissue...