I never thought about the vacuum, I have a lid but there is a hole in it so the water can go in it has a plug for it I just have to find it......
they are clean but they still will either leak constantly or not give any water.
It sounds like your waterer might have low-quality nipples.

I made my own waterers with the horizontal nipples made by Rent-A-Coop. (Tip -- don't use the drill attachment to install them, put them in by hand to avoid cracking the plastic container).