[Hammy992]

I've found that the 125ml small bottle I have works best by filling it and leaving some space at the top, but my large 500ml bottle with a longer spout needs to be pretty much filled all the way to the top or it just drips and drips. I discovered that when a section of bedding underneath it where my ham's food stash is started smelling damp.
I think with some of the bottles the ball bearings are a bit dodgy and don't always stop the water/allow water through. As long as you have more than one or even if you use a shallow dish there will always be a water supply available. Just remember if you're using a dish to put it on a flat surface where it can't be spilt or have bedding kicked into it.