I realized that my gliders weren't drinking from their water bottle quite awhile back. I remember reading a thread on here about the type of ball that some bottles had on them. I checked and sure enough mine had it so I had to go buy a new one.
The difference is the spring loaded ball on the end or the ball that's just there and can easily be touched to get out water. The ones that have the spring in them are to hard for gliders to use. They can't push the ball to get water out.
Just to update about the different types of water bottles.