Protecting coral reefs with Nemo-Pi, the underwater monitor
The German charity Save Nemo works to protect coral reefs, and they are developing Nemo-Pi, an underwater “weather station” that monitors ocean conditions. Right now, you can vote for Save Nemo in the Google.org Impact Challenge.
Save Nemo
The organisation says there are two major threats to coral reefs: divers, and climate change. To make diving saver for reefs, Save Nemo installs buoy anchor points where diving tour boats can anchor without damaging corals in the process.
- Anchors damage corals.
- Buoys are safe anchor points.
In addition, they provide dos and don’ts for how to behave on a reef dive.
The Nemo-Pi
To monitor the effects of climate change, and to help divers decide whether conditions are right at a reef while they’re still on shore, Save Nemo is also in the process of perfecting Nemo-Pi.
This Raspberry Pi-powered device is made up of a buoy, a solar panel, a GPS device, a Pi, and an array of sensors. Nemo-Pi measures water conditions such as current, visibility, temperature, carbon dioxide and nitrogen oxide concentrations, and pH. It also uploads its readings live to a public webserver.
The Save Nemo team is currently doing long-term tests of Nemo-Pi off the coast of Thailand and Indonesia. They are also working on improving the device’s power consumption and durability, and testing prototypes with the Raspberry Pi Zero W.

The web dashboard showing live Nemo-Pi data
Long-term goals
Save Nemo aims to install a network of Nemo-Pis at shallow reefs (up to 60 metres deep) in South East Asia. Then diving tour companies can check the live data online and decide day-to-day whether tours are feasible. This will lower the impact of humans on reefs and help the local flora and fauna survive.
Nemo-Pi data may also be useful for groups lobbying for reef conservation, and for scientists and activists who want to shine a spotlight on the awful effects of climate change on sea life, such as coral bleaching caused by rising water temperatures.Vote now for Save Nemo
If you want to help Save Nemo in their mission today, vote for them to win the Google.org Impact Challenge:
- Head to the voting web page
- Click “Abstimmen” in the footer of the page to vote
- Click “JA” in the footer to confirm
Voting is open until 6 June. You can also follow Save Nemo on Facebook or Twitter. We think this organisation is doing valuable work, and that their projects could be expanded to reefs across the globe. It’s fantastic to see the Raspberry Pi being used to help protect ocean life.
5 comments
David
If recently introduced legisltation in Hawaii is a reliable indicator, the Nemo-Pi project needs to extend its sensing to include oxybenzone. In addition, it would be worth detecting levels of petroleum in the water – another known disruptor of marine endocrine systems and thus another cause of coral decline. As if that wasn’t enough for the corals to contend with, there’s also estrogen-like compounds leeching from plastic debris, and the plastic itself being consumed by the coral’s creatures.
Janke
Damn this is awesome. I grew on the ocean and love its majestic beauty in all aspects such as the reefs. So this project makes me proud and hope everyone votes for it.
Dee
@All
We are still looking for programers helping us with the core code of the pi-zero. Contact:nemopi@save-nemo.org
@David:
We know about the problems around estrogen compounds. Like many other chemical sensors the development / modification are extremly expensive. But we are working hard to extend the list of supported measurement units.
@Janke:
Thank you for your words. YES – voting is very importand. Only a few days left :-)
Bill Gallagher
Where can I build or buy the sensors to have monitoring of a river near Boston, MA ??? It a great project Save Nemo!!!!!!
Dee
Hey Bill,
you cannot buy our sensors right now. They are still in beta-testing stage. But you can leave a message to our tech-team. Contact:nemopi@save-nemo.org
Regards Dee