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Preliminary Research and Documentation

The following research and documentation is meant to get this project started. Please consider this a work in progress. Significant work is needed to move this project forward. 

Reproduction in Corals

Corals employ two different methods of reproduction. Sexual reproduction, and asexual reproduction. 

In sexual reproduction, coral gametes (eggs and sperms) are released (spawned) into the water. When the eggs and sperm come together, they form a genetically unique coral colony. In asexual reproduction, pieces of a coral colony break off and grow into new colonies. This method is also known as budding. These corals grow identical to the coral from where they broke off. Often known as clones, these are genetically identical to their parent colony. 

Restoring coral colonies can be done by using these 2 methods to either grow corals in a lab and plant them on the sea floor or directly restoring them under water.


coral gardening using Micro Fragmentation

Micro fragmentation is a technique of growing coral in a lab. Live corals are broken down into smaller pieces that contain about 5-6 polyps and placed in sea water tanks at about 25 °C. This stimulates the coral tissues to grow into clones. These clones when brought together recognize each other and fuse with one another to form larger coral. 

Naturally occurring corals take years to build. With micro fragmentation, large coral colonies can be built in weeks. After 6 months these fully grown reefs are ready to be planted back on the ocean floor.


Figure 1 - Micro fragmentation in a lab.


3D Printed Corals

Corals can be printed using special 3D printers. This is the most commonly used technique in the world. 3D printed corals are printed in a lab then then assembled and installed on ocean floors. 


Figure 2 - 3D printed coral in a lab.

More information on 3D printed corals is available here.


restoration by larval enhancement

Also known as coral reseeding, restoration occurs by sexual reproduction in this technique. A large number of competent larvae is placed directly into the coral reef substrata. This allows for the gametes to seek each other and form new colonies.  This method is capable of producing large scale coral colonies over time. Mass coral spawning events occur only 1-3 times in a year, these can provide millions of baby corals – each of which represents a new genetic coral colony.

This technique can also be used to restore coral reefs without removing them from the ocean floor.

The coral larvae are microscopic in size and vulnerable to natural factors like temperature and water currents. Extra care must be taken when employing this method for restoration.


BiorockTM - Mineral Accretion Technology - 

Mineral Accretion Technology, or more popularly known as BiorockTM is a technique of growing and restoring corals by inducing a small amount of electric current. 

A girder or a metal wireframe is placed on the seabed or near a coral reef and a DC current is applied to the frame. Parts of corals that have polyps are then deposited on the girder. Once the live corals stick on to the frame, they start growing again. 





This project is being developed as an open-source project with the following licensing: