+1 on the anxiety when hanging out over deep water. There’s an ancient part of my mammalian brain that says ‘something can come up from the deep to get you’! Also, there’s just not a lot to see when you’re hanging out like that. Once, in Cozumel, two sharks did come up out of the deep. I suspect they were reef sharks but even with video we were never quite certain. Give me shallow water with lots of light for macro and I’m happy as a clam. 
