Image credit: Reef Design Lab
As oceans get warmer, coral reefs are struggling. Coral bleaching occurs when the thousands of coral polyps that make up the reef become stressed by outside factors. Enough stress, and enough bleaching, could cause the coral to die.

Image credit: Reef Design Lab
In order to prevent the mass bleaching that is impacting our coral reefs, a group called Reef Design Lab is making sandstone reefs to replicate pleasant conditions for the polyps. In particular, soft white and pink colors appeal to baby polyps, which see them as signs of a healthy reef. Tiny crevasses and caves also give the polyps a place to stay where they will be safe from predators.

Image credit: Reef Design Lab
In June, Popular Science highlighted Reef Design Lab’s work on 3D printing artificial reefs. A porcelain coating on the outside of the organic-looking structure replicates the chemical signature of the coral to which the polyps are used.
Image credit: Reef Design Lab
Filed Under: Materials • advanced