I had my 1 week post-op MD visit today - I am very fortunate that my doctor's regamine is 2 days of Clear Liquids followed by 2 weeks of full liquids which can include thinned out oatmeal, runny mashed potatoes, small curd, low fat cottage cheese and cream soups (strained). I have lost 5 pounds since surgery and only feel hungry when it's close to meal time. I find that if I don't drink my Water or other clear liquid like I'm supposed to, I do feel a bit hungry in between meals - so I would say keep the fluids coming!
I also have been told that the pouch will not stretch because of liquids, they run right through. Which is why you are supposed to wait AT LEAST 30 minutes before drinking after eating - the liquid will flush the food through quicker and you will end up feeling hungry faster.
Good luck friends - stay strong - it HAS to be worth it in the end.