This may be of importance to anyone using this kind of valve, even in systems that have no tubing.
A couple of days ago Kulu decided to dislodge his water nozzle and chew through the tubing. I thought it was just him being his little destructive self, getting bigger, and finding new ways to get into trouble.
I measured his water level the next day and found he didn't drink anything. He could have been without water for 48 hours since I could not get a reading the day before after it drained out through the chew holes. Apparently he did this because it wasn't dispensing water.
I should have checked it when I refilled it. The valve was totally clogged. I took the valve assembly apart and found wet chinchilla hair that had spilled out into my hand. It appeared to have been wrapped around inside of the valve where I found more hair. My guess is that it came from the funnel I used to fill the reservoir and it may have built up over time.
There probably isn't a good way to prevent that but I will be more vigilant to make sure the water is dispensing each morning.
To keep Kulu from dislodging the water nozzle again I made a new modification. The problem was the nozzle is attached to the bars by a spring-like clamp designed for small gauge wire cages having a 1/2" x 1" bar spacing. It is not as secure on the large bars I have in the parrot cage. He managed to pull the valve into the cage and ate a 2 inch section out of one side of the hose. It was the by the grace of God he did not get sick from that. In the diagram you can see how the clamp can be rotated against the vertical bar and dislodged by a fidgety rodent.
I repaired it by installing a clamp next to the water nozzle bracket that simulates a second vertical bar. You can see how it's arranged in the attached diagram below (color coded green) with a bolt and nut (color coded blue) through it to tension it to the bars. It was fashioned from an electrical conduit fastener with the ends bent outward. So far it has been trouble free.