When I first started smoking I always used a water pan and I always fought temperature issues. I finally quit using water and I didn't notice any difference in the moisture of my cook and my temperature problems went away. You could try using less water but I believe it will just boil off and you'll end up with a big temp swing, add more water and the temp drops and so forth so on. I've only saw a couple of commercially built water smokers and they both had a pretty good size firebox, I believe that's what it takes to be able to use a lot of water and not fight the temp swings. jm2cw