Sorry to be late with this answer, but my computer had to go in for a radical upgrade, and when I got it back, it took me ages to find my way back in to all the settings on sites like the Answer Bank. Which then kept me locked out because I couldn't remember my password, and none of the help I got was any use. Finally got back in half an hour ago.
SO: when I took 20-year-old Sindy Flagtail to the Blue Cross last year, because she was leaving much of her food uneaten, they asked me if she drank much water, and I told them, not a lot. The vet said that it would be a good idea to put water in with her food - not to deluge it, just a dribble from the cold tap, so that it can be swirled around and be absorbed amongst the chunks. She now eats all her food, and the water disappears too. Result! Try it!