[racinghamster]

I agree with filling them right to the top. It helps the vacume inside the bottle. Once you turn it up the right way, it`s important to tap the ball-baring a few times to release the water. If it seems slow to come out or doesn`t come out, take the bottle top off again and spill out just a little of the water. Screw the lid on again but not too tight. Tap the bottle again in it`s correct position until it releases water properly and do so again once hung in the cage, just to double check. You will get the odd bottle that does cause issues. I usually don`t trust those and replace them right away. A bottle should work well at all times.