This happens to me all the time now, the less I eat, the more output I have & it's all "water". But I have a problem with staying hydrated to the point that I have to have daily IV hydration at home. I just loose so much, and it's caused me to become hypovolemic a number of times. Really be careful about what you are taking in,and how much you're loosing on a daily basis. If you can, go to any local pharmacy and pick up a urinal (like the ones they use in the hospital to empty your bag and measure your output) I prefer the men's urinal with the lid. I always keep atleaast 2 handy for the times when I am so weak that I can't get out of bed, but my bag is so full that it will "blow" if I don't empty it ASAP.
Anyway, I'm totally getting off track now. My point was to get it so that you can measure your output for a few days, and if you are loosing MORE than a ltr (1000 ML's) like closer to 2000 ML's per day, (also very important to keep track of EXACTLY how much fluids you drink and what.) If you are loosing more than what you are taking in than that's obviously a problem, but the problem will be in how much MORE.
Color doesn't mean anything really. And I wouldn't focus too much on the amount of calories you're eating, from what I've learned, having an Ilestomy, and high output, possibly "dumping syndrome" could be a small blockage keeping the "food" from passing and only "water like" output. This happens to me all the time (every thing that I eat) There's so many things that it could be.
So I would start with the amount of output vs intake. Keep good record's and get an appointment with your GI Dr. soon if you feel like things don't add up and especially if you are having pain.
Nora aka Crohnies4Nora