WaterElf – an open-source aquaponics monitoring and control device

WaterElf is a micro-controller with built-in wifi, a bunch of sensors, valve controls, electrical socket switching and data logging to the cloud. Here’s the last prototype to emerge from the lab into the wild:

WG waterelf

Adding a WaterElf to aquaponics means you can ensure that the key water parameters such as pH and water temperature stay in the correct ranges. The WaterElf also senses the air temperature, humidity and light levels – so that you can match what you grow to your conditions. As well as all that, the Elf can also sense the water level in up to 3 grow beds – opening up the ability to set different flood-drain levels for each bed independently.

The WaterElf can control up to 16 electrical sockets by radio – so you can use this to control pumps, lights, fans etc. You can also control up to 3 of our water valves with the Elf, this is useful in larger systems such as those based on the FAO design.

We’ve been refining the design of our system since 2013 when our first prototype was installed at the Incredible AquaGarden in Todmorden. We’ve been on an incredible journey and learned a lot about what does and doesn’t work in a busy, challenging environment with lots going on.

Because the WaterElf sends the data it collects to our database in the cloud, you can see a summary dashboard on your phone or computer anywhere in the world. If you’ve got the Raspberry Pi control center with fish-cam (the Grow Hub) then you can also see the fish in real-time! And having the ability to share the current state of your system with other growers in our community means that if you need help then it’s only a click away. We’re excited about building a knowledge base of what grows well under which conditions – using the power of citizen science. Of course if you’d prefer not share your data then you can turn this off – but we hope you choose to contribute.

Like almost everything we do, the designs of the WaterElf are open source. We believe the problems facing our communities and our planet are too important, and too urgent, to avoid tackling right now. Open source allows us to be small and yet work collaboratively towards big solutions to big problems. It sidesteps all the barriers of licensing and patents. It means that we can work flexibly with others such as Open Source Ecology, Farm Urban and Aquaponics Labs – focusing on the engineering not the contracts. It gives us a curating rather than owning relationship with our technologies that keeps us centred on meeting the needs of the community.

We don’t see people using the WaterElf as passive consumers of a tech gadget – we’ve done everything we can with its design to try to make it a springboard into a community of growers. With every report of success or failure with one crop or another, the shared knowledge pool gets bigger and more valuable. Join in, grow some fresh food and find out just how much fun it can be.