Clownfish in their anemone on a metal structure, part of the Biorock reef project in Pemuteran. ..A low voltage direct current is applied on metal structures using an anode. Once the reef structure is in place and minerals begin to coat the surface, the next phase of reef construction begins. Divers transplant coral fragments from other reefs . Immediately, these coral pieces begin to bond to the accreted mineral substrate and start to grow—typically three to five times faster than normal. Soon other marine life starts colonizing the structure as well...Some say the effort is severely limited. While the method may be useful in bringing small areas of damaged coral back to life, it has very limited application in vast areas that need protection.