It's impossible to start off this review without just saying how amazing the lighting is. It also blows my mind that you managed to get everything so sharp in such a dark environment. It's hard to critique this kind of photo without having been there. I might have tried moving the shot up a bit to get rid of the lighter rock bottom center, it somewhat draws the eye, and I feel like it somewhat detracts from the picture as a whole. I'd be curious to see the shot cropped with the white rock cut out, the different dimensions might make the picture pop even more.
But this is just me nitpicking, it's hard to find things wrong with the picture, but that IS what a critique is. Overall, stunning shot!
Wow, how beautiful! I was wondering if it was oil or if it was white sand on the bottom but that probably wouldn't have been so visible... but even though oil in the sea is bad this is totally gorgeous!