Giant clams love light. As a general rule, the more light they can get for their symbiotic algae, the better. Which makes the "devil clam", Tridacna mbalavuana from Tonga and Fiji so weird. It lives up to 100 ft down! https://www.inaturalist.org/taxa/479982-Tridacna-mbalavuana (364)
Devil Clam (Tridacna mbalavuana) · iNaturalist
Tridacna mbalavuana, the tevoro clam, is a species of bivalve in the family Tridacnidae. It is found in Fiji and Tonga. It is currently listed on the IUCN Red List of Threatened Species (Source: Wikipedia, '', http://en.wikipedia.org/wiki/Tridacna_mbalavuana, CC BY-SA 3.0 . Photo: (c) James W. Fatherree, some rights reserved (CC BY-NC), uploaded by James W. Fatherree)
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