BioRock

Picture credit : Simon Dowling

The BiorockĀ® method was invented through a collaboration in the 1980’s by Professor Wolf Hilbertz and Dr. Tom Goreau of the Global Coral Reef Alliance.

By applying a low voltage electric current to a metal structure (our one is made from Rebar) , minerals present in the seawater around the structure would form as solids and adhere to the structure. Main minerals are Calcium Carbonate and Magnesium Hydroxide. Calcium Carbonate is the key mineral for coral reef structures. Due to the Biorock electrolytic reaction aiding coral growth, research has concluded that coral fragments can grow up to 5 times faster on a Biorock than in a natural state. The electrical field that is emitted and the structure itself, tends to attract fish and invertebrates in a very short period of time. This creates an ecosystem that can thrive in areas where coral reefs had previously been destroyed.

In 2008, Koh Tao Eco Warriors banded together with a proposal to build a Biorock. At the time it was patented technology and as such, would eventually cost 1,000,000 THB for building, licencing fees, equipment purchasing and consultation fees. The funds were raised locally by fund raising events, including the Koh Tao Underwater Festival.

The structures were built in and deployed towards the end of the year, and coral transplanting commenced at the beginning of 2009. The Koh Tao Biorock design was essentially 4 large domes with rippled fencing running between each dome to create more surface area for fish and coral. To get good research, a control dome which was not connected to the circuit was also put down to monitor growth and survival comparisons. A power cable was fed to the underwater generator from a generous donor situated on land near to the dive location.

Over the years, essential maintenance had to be carried out. Algae and predator removal helps to enhance the site and improve coral health and growth. Also, the technology to run the Biorock has to been regularly checked. Many times the Biorock stopped working for various reasons and fixing it was very difficult due to the patent rights.

Now, in 2017, the Biorock is flourishing with life, and has many unique creatures around its site. Situated in between Koh Tao and Nang Yuan Island it benefits from good current and minimal diver impacts. Also, now the patent has expired, we are able to look at alternate solutions and building concepts to enable us to create more Biorock structures without the huge cost involvement.

To get involved with coral transplanting and monitoring at the Biorock, Check out our Eco Internship pages.