Have had this printer (I love it) just over a year.
I have been gradually replacing Epson cartridges with Fotospaeed Inkflow without any problems.
Recently, I decided to try a thin artpaper - loaded it from back (should have been front) and LK black ran out half way.Since then, 2 of my black nozzles are blocked and after having run nozzle cleaning etc - blockage getting worse.
I thought maybe I had replaced LK with the wrong black ink so I borrowed a Epson LK refill and put it in - and its not recognized - another complication.
I have an exhibition shortly...…..
update: this has been sorted as turned out it was air in the tubes.