Reef-building corals are bleaching and dying at unprecedented rates due to ocean warming. However, corals bleach at very different rates- why? Corals are association of animals and symbiont algae that feed them. Some corals have skeletons that scatter light back to their algae much faster increasing light availability but that increases their risk of bleaching. We want to identify the skeletal morphological characteristics that may increase the risk of bleaching to better protect coral reefs.