I need to monitor the level of several tanks containing heating oil/diesel. At the moment I am using a simple dip stick. However, I would like to monitor these electronically. I did some experiments with an ultrasonic range finder, but it wasn't accurate enough for various reasons. Has anyone got any suggestions for a suitable sensor that would interface with a Pi.
I don't just want a low level warning, but something that can tell me the height of the liquid in the tank, so I can monitor the rate of consumption. I have had a look around for some sort of float monitor, but can't seem to find anything out there.