Blog posts can be found at: https://www.iot-experiments.com/tag/water-tank-project/
This source code requires:
- RF24 [#433] v1.1.6: https://github.com/TMRh20/RF24
- NewPing [#176] v1.7: https://bitbucket.org/teckel12/arduino-new-ping/wiki/Home
- LowPower [#38] v1.60: https://github.com/rocketscream/Low-Power