Have you considered a self-refilling (I forget the exact name of them, but they’re advertised for cats) bowl? Your bunny prefers a bowl because they are able to drink much more easily that way. A self-refilling bowl will be weighted enough so that your rabbit cannot tip it over. How was he getting it dirty?

I’m not sure that there is such a thing as a water bottle that doesn’t leak or drip. Most rabbits really prefer to drink out of bowl. Heavy crockery bowls are the best. If some hay is getting in the water, that wouldn’t be too bad. If poop or pee was getting in the water, it sounds like his litter box may be too close to the bowl. Is his cage or pen large enough so that the litter box can be some distance away from the water bowl?

I use the metal ball kind. I haven’t found brand much matters. I have used them for decades, not just the big one I have for Porky, but I’ve had them for countless other animals over the years. All the way down to a tiny deer mouse.

My experience with bottles is that filling them fully, then making sure they are hanging at the right angle is what prevents dripping. Tapping the ball, will also often stop initial dripping when hung. I also tap when I first hang the bottle even if it isn’t dripping just to make sure it works.

I agree with Eepster. Just make sure to fill it to the full, right angle and tipping the ball.

Redford likes to drink water only from bottle and Bianca from the bowl so by now I have experience with both.