morning update:
This morning when I opened the pop doors, I checked the water level and it had hardly changed at all from the night before when I closed them in. Yesterday during the day, the level did go down a good amount, though. It still doesn't seem like enough to me, and so I'm still worried.
It rained all day yesterday until around 5pm, when I finally let them out to free range. A few of them found a dish with some rainwater in it and drank like crazy again. The others did not.
I am still worried that some will not figure these new waterers out. How long can I push it with no other water source in order to force them to learn? If some are truly dehydrated because they just can't figure it out, will I be able to tell? I really, really don't want to walk out and find a dead chicken because I didn't provide it with water. I couldn't live with that...
I'm hoping that since most of them seem to be getting it, that eventually they all will... but I don't like to gamble with their health either...