I use the water converter from Madan (in my site
). I buy the carton of Smartwater from Costco & screw it on, that's it. No mess to clean up, no spilled water. When the bottle is done, I just recycle it & screw on a new one. I always keep fresh water out for them in a stainless bowl, but Mimi prefers not to get her facial hair wet. The only down side to the water converters is that it needs to be attached to a crate, gate or ex-pen.
You can also screw it onto a wall, here's a customer's pic:
There's a quick release clasp, so the bottle is easy to replace or refill. Since the design of the converter is closed, no bacteria & the water stays clean.