3D printing frames a restoration for coral
Restoring corals could become easier and faster through the use of 3D printing. As the technology matures, it could be used to quickly and reliably create support structures on which corals can grow.
Coral reefs around the world are suffering from warming oceans and increasing pollution. Reef restoration efforts use concrete blocks or metal frames as substrates for coral growth. The resulting restoration is slow because the corals deposit their carbonate skeleton at a rate of a few millimeters per year.
Charlotte Hauser and her team explore the use of 3D printing to speed up the process. “Coral microfragments grow faster on our printed or molded calcium carbonate surfaces that we create so that they can grow because they don’t need to build a limestone structure underneath,” says Hamed Albalawi, the one of the main authors of the study. In essence, the idea is to give the corals a head start so the reef can recover faster.
The idea itself is not new. Researchers tested several approaches to imprint coral support structures. However, most of the efforts have used synthetic materials, although work is underway to use hybrid materials. The team developed and tested a new approach called 3D CoraPrint, which uses an eco-friendly and durable photo-initiated calcium carbonate (CCP) ink that they also developed. Aquarium testing has shown CCP to be non-toxic, although researchers are planning longer-term testing.
Unlike existing approaches, which rely on passive colonization of the printed support structure, 3D CoraPrint involves attaching coral microfragments to the printed skeleton to initiate the colonization process. It also incorporates two different printing methods, both of which start with a scanned model of a coral skeleton. In the first method, the model is printed, and the printing is then used to pour a silicone mold. The final structure is produced by filling the mold with CCP ink. In the second method, the support structure is printed directly using CCP ink.
Both approaches offer complementary advantages. Creating a mold means that the structure can be easily and quickly reproduced, but the hardening process limits the size of the mold. Direct printing is slower and lower in resolution, but allows for individual customization and the creation of larger structures.
“With 3D printing and molds, we can achieve both flexibility and a mimicry of what is already happening in nature,” says Zainab Khan, the other lead author of the study. “The structure and the process can be as close to nature as possible. Our goal is to facilitate that.
– This press release was originally posted on the King Abdullah University of Science and Technology website