Bell Siphon Rain Gauge

Bell Siphons are frequently used in aquaponics and fish tanks to automatically empty tanks when the water level reaches a certain height. Only natural forces are used to empty the tank relatively fast. The Siphon has no moving parts. If you attached probes connecting the outlet of the bell siphon and a microcontroller or Raspberry PI, you have a solid state rain gauge

See https://www.instructables.com/id/Bell-Siphon-Rain-Gauge/ for build instructions, python code etc.

To see the rain gaug