Cellulose Nanocrystals and 3D bioprinting are being used to create bionic corals capable of growing microalgae by mimicking coral tissue and its underlying skeleton. This bionic 3D material is able to replicate the optical and mechanical properties of coral and is demonstrated to provide a microenvironment suited to coral-algal symbiosis required in healthy coral reefs. The 3D printed material has the potential to further research into coral-algal symbiosis research, such as photobioreactor designs, as well as be of benefit to coral reef conservation efforts.