Acroporidae and Pocilloporidae are the predominant reef-building corals
of Indo-Pacific coral reefs. Coral colony is the basic geometric
construction of coral reef, while sustained formation of their calcium
carbonate skeletons is the heart of healthy reefs. However, the reef
forming strategies in coral growth is still obscure. In this study, we
reconstructed 32 representative samples using high-resolution computed
tomography and created canal networks inside skeletal data to
investigate coral growth regulation and related parameters. In Acropora
and Montipora colonies, the polyps are connected as an integral network
by complex canals that perform and regulate physiological processes
including budding, branching, and mineralising. Furthermore, we
visualised coral growth axes and rings, revealing colony growth pattern
regulation. We also drew a skeleton grey-gradient heat map and
calculated coral skeleton ratios to reveal skeletal diversity, devising
a method to quantitatively analyse coral growth. On the basis of the
canal network reconstructions, we hypothesised coral growth strategies
and compared the similarities and differences among the four genera.
This work extends the knowledge of how corals grow their skeleton, what
the major controls are and how skeletal growth varies amongst species,
ensuring further protections of tropical coral reefs.