I have made a video to give you an idea of how our Tank Water Level Indicator works.
It is definitely not very professional but you'll get the general idea
of how it would work on your full size tank.
In the video the "tank" is an old 20 litre plastic drum which has a vertical clear section so you can see the water inside it as the level goes up and down.
Unfortunately working on such a small scale its a bit hard to get everything completely accurate but as you'll see its pretty close!
It runs for about 3 1/2 minutes.
If for some reason the video doesn't work, you can view it
on Youtube at this LINK
If you don't like to click on links, search for
"tank water level indicator lucano"