Indonesian Corals Grow With Help From an Electric Current

All photos: YouTube screen grabs

Corals have a whole heap of problems to deal with -- pollution, marine debris, warming water due to climate change, overfishing of important species that keep reefs healthy and so on. But there's one human technology that is helping, rather than harming reefs in Indonesia that are on the brink of dying out.

Discovery News writes, "In the turquoise waters of Pemuteran off the north coast of Bali where the project was launched in 2000, a metal frame known as "the crab" is covered with huge corals in shimmering colors where hundreds of fish have made their homes."

That "crab" cage is electrified, and a small, harmless electrical current is helping to stimulate growth. In fact, corals can grow 2-6 times faster on these cages than on other natural surfaces.

Rani Morrow-Wuigk, a 60-year-old German-born Australian used technology created by German architect and marine scientist Wolf Hilbertz in this area to bring back the corals.

Hilbertz had sought to "grow" construction materials in the sea, and had done so by submerging a metallic structure and connecting it to an electric current with a weak and thus harmless voltage. The ensuing electrolysis had provoked a build-up of limestone, in a kind of spontaneous building work. When he tested out his invention in Louisiana in the United States, Hilbertz saw that after a few months oysters progressively covered the whole structure, and colonized the collected limestone. More experiments were carried out and the same phenomenon was confirmed for corals.

Called Biorock, the technology has some real potential. Rani set up 22 structures at first, which were successful enough that now around 60 cages are set up in Pemuteran bay. The structures seem to help the corals resist warming temperatures and other stressors that would otherwise wipe them out -- and staving off bleaching is one of the most important factors in keeping coral reefs alive.

Discovery News reports that the technology and the resulting bounce-back of the corals has helped bring in tourism and boost the fishing industry, so it is a winning technology for everyone.

Take a few minutes to watch the video of this reef. It's worth it.