Great video about a fascinating subject. I’m convinced that there is a lot to this. We’ve taken tiny samples of different water layers near Porites colonies at multiple sites in French Polynesia and had them analyzed by Reef Labs for differences in water chemistry. To be honest, I wasn’t really expecting to see anything of note. But to our surprise, in my discussion with Gene at Reef Labs, there appeared to be a significant and pretty consistent difference between samples obtained just over the coral surface and those obtained a few feet above the coral (differences in phosphorus concentration in particular). These results were especially shocking as there should have been substantial mixing taking place between these water layers because the wave action typically was almost strong enough to knock you off your feet. I get that there are many other factors at play, such as PO4 uptake by plankton, dilution by rainwaters at the surface, etc. Regardless of the true cause(es), this stuff really makes you look at corals in a different way. Outstanding report, Brandi.
