History and Technology of Nurtured.Co Artificial Reefs
The story so far…
Nurtured.Co creates living artificial reefs using a process based on decades of research from renowned marine biologist and biogeochemist, Dr. Thomas Goreau. This process encourages mineral deposition and coral settlement by introducing an electrical current to the artificial reefs through the electrolysis of surrounding seawater. Traditionally known as Biorock®, this process has been successfully used across the globe and particularly in Indonesia. The Biorock® process was first discovered back in the 1970’s when material scientist Wolf Hilbertz tried to develop self-growing construction materials for architectural purposes. The material was at that time referred to as ‘Seacrete’ or ‘Seament’ and was soon renamed as Biorock® to emphasise its capacity to grow larger and stronger marine construction material with age . Corals grown on Biorock® artificial reefs have shown increased survival and growth rates due to the process enabling successful replication of coral reef foundations.
The Nurtured.Co method uses the basic principles of Biorock® but at a more portable and scalable rate. Nurtured.Co implement an alternative power supplying method which enables the creation of these advanced artificial reefs in environmentally sensitive regions where electrical cabling cannot realistically be installed and in much more remote areas where this infrastructure is not available.
How do corals grow on a Nurtured.Co artificial reef?
When a Nurtured.Co artificial reef is first installed, fragments of coral found in the local area are attached securely to the structure. This gives these corals a strong foundation and substantially increases their growth and survival rates. The power supplied to the reef is at a low intensity and instigates the precipitation of calcium carbonate onto the structure. Soon the corals tied to the reef start to bond to the structure. The calcium carbonate continues to strengthen over time and the coral fragments begin to branch out and expand. Coral larvae will also settle onto the artificial structure after a coral reproducing event and begin to form new corals. Typically, when corals first spawn, a large amount of their energy is spent attaching to a natural reef. On a Nurtured.Co reef with an existing energy support, coral spawn can spend much less energy on foundation bonds and more energy on growth. The result is faster growing and more resilient coral.
Technology and Power Generation
To generate the electric current needed to stimulate faster coral growth and settlement, traditional Biorock® reefs use land-line cables. These cables are secured to the seafloor and need to travel from the location of the artificial reef to a land-based generator or other power source. There are challenges using this approach as it requires the artificial reefs to be positioned in areas where electrical infrastructure is readily available or easily created. There are also risks involved in the use of extensive submerged power cables and in some regions such as the Great Barrier Reef these methods are prohibited.
Whilst using land-line power cabling is problematic in the Great Barrier Reef, there are alternative methods. On-site power generation is key to providing the required electrical currents without the extensive electrical infrastructure requirements of power cables. To generate power for each structure, Nurtured.Co uses a replaceable sacrificial anode that reacts with the surrounding seawater to provide a minor electrical current. This allows for portable installation as each artificial reef acts as its own separate unit. The materials used in the sacrificial anode are naturally occurring in seawater and produce no negative consequences for the surrounding environment or ecosystem.
In the future, Nurtured.Co aims to employ more advanced techniques of on-site power generation such as the use of renewable energy. Solar panels and small tidal turbines could possibly be integrated into future projects, but further research and development is required to find the best possible practice in installing and utilising these methods at low cost.
What does Nurtured.Co technology mean for coral reefs?
- Reef restoration in rising water temperatures
Nurtured.Co artificial reefs provide hope for the restoration of more regions of coral reef as these structures are proven to have substantial benefits for both corals and their surrounding ecosystems. One of the biggest threats to the Great Barrier Reef is climate change and increased global warming. Increased ocean temperatures result in a rise in ocean acidity and this has dramatic effects on the health of coral reefs. Nurtured.Co artificial reefs directly combat these adverse effects from global warming as the electrolysis reaction promotes a decrease in acidity in the surrounding water. Localised pH increases allow corals to spend less energy creating limestone skeletons and more energy on growth and expansion. Corals grown using these methods have previously shown growth rates of 2-10 times faster than natural counterparts . In addition, these corals are much more temperature resilient and able to withstand extreme weather events due to the strong foundations provided.
- Increased coral settlement and reproduction
The benefits of these advanced artificial reefs also include increased coral settlement and reproduction. Calcium carbonate is a limestone substance that makes up the foundation of coral reefs and coral skeletons. The presence of this substance on Nurtured.Co structures allows corals to attach directly to the limestone, replicating natural conditions. This allows corals to conserve energy normally spent on extending their limestone skeletons and redirect this energy to growth and reproducing. Coral spawn can settle on the structures easily as there is less spatial competition compared to the natural reef and each artificial reef has an arcing structure to elevate corals slightly from the sea floor. Elevated corals experience less sediment build-up and increased water quality, leading to improved health.
- Increased marine life
Coral reefs provide food and shelter to many species of marine life and a revitalised reef environment will encourage a significant rebound in fish populations. As coral reefs grow and recover, so will the marine ecosystems. Large schools of migratory fish will begin to reinhabit previously damaged reef environments where a Nurtured.Co reef has been strategically positioned.
- Protection from erosion
Nurtured.Co artificial reefs also act as natural erosion protection for other reefs and beaches. The arcing structures used in the designs can slow down and break waves, reducing the total energy of waves that crash onto other reefs or surrounding beaches. Similar arcing structures from other artificial reefs have showed great success in returning sand to beaches around the world and preventing further coastal land loss.
 T. Goreau, Marine Electrolysis for Building Materials and Environmental Restoration, In-Tech Publishing, 2012.
 P. Prong, T. Goreau, "Biorock Electric Reefs Grow Back Severely Eroded Beaches in Months," Journal of Marine Science and Engineering, 2017.