I’m excited to share my latest DIY project: a Water Tank Monitor that I’ve been working on over the past few months. This compact device monitors water levels in my 5m³ tank, displays data on an OLED screen, and integrates seamlessly with my Home Assistant setup via Zigbee.

Water Tank Monitor PCB

The goal was to create a compact, self-contained device that would monitor water levels using an ultrasonic sensor, display real-time data on a 0.91” OLED screen, log data via Zigbee for smart home integration, and fit within a Legrand Mosaic obturateur for a clean, professional look.

This project demonstrates how modern DIY electronics can create practical, professional-grade IoT solutions. The combination of custom PCB design, embedded programming, and smart home integration showcases the full spectrum of skills needed for modern hardware projects. The Water Tank Monitor is now successfully monitoring my water tank and providing valuable data to my Home Assistant setup. It’s a great example of how open-source tools and community knowledge can enable sophisticated DIY projects.

Open Source & Documentation

All project files are available on GitHub:

The repository includes:

  • Complete PCB design files (KiCad)
  • Firmware source code (PlatformIO)
  • 3D models and assembly documentation
  • Detailed build instructions

For more details about the technical implementation, challenges faced, and solutions developed, check out the full project documentation on Hackaday.io.