I prefer ice or ice water in a bong/bubbler. It cools the smoke very nicely. I prefer the ice though. I can just slide a few cubes in the top of my bong, and when I'm done, just take them back out with very little water drainage in my bong. Usinh water I find kind of fogs up my bong and has a musky taste after, so I like ice or the infamous rice (dry) in my bong.