Over here in Aus it gets pretty stinking hot and I've got two dogs who love to play in their water bowl (100L kids clam shell) and they'll routinely empty it in a single day which on 40°C days can be terminal.
So what I'm wanting to do is make a large concrete basin to fill with water, measure the level of the water and have it fill when it gets below a certain level.
I'm a little stuck on the best way to measure water. I've seen the ultrasonic method but because I'll have live animals going in and out and a water level that can slosh around I think that would be unreliable.
What I had in mind was simply having a fail off sort of connection where it will detect water on a sensor of some kind and when that sensor no longer detects water it will flip a solenoid connected to my water mains that will open up while it gets a high signal from hte arduino and close when it gets a low signal.
The only question the arduino needs to find out is "Is there water?" "yes/no" which should simply things and I'll just mount whatever sort of sensor I use to a point I want it to start filling from.
Does anyone have any suggestions?