Thanks to Larry from Summit Divers for the fantastic photo.
I was shooting Pulsating Xenid.
The pulsating xenid (Heteroxenia fuscescens) is a species of soft coral in the family Xeniidae.
Polyps pulsate rhythmically about 40 times per minute. They move their tentacles in a “pumping” or “pulsating” fashion. This function of pulsing is currently undetermined. Some scientists suspect it is a method for the creature to create a current for feeding, respiration, and/or helping to dispose of waste and detritus.
Here’s video of what I was shooting in the above photo.
The images in the video was shot with a Panasonic GH5 – Here’s a link to my underwater set-up.