Cuz generally all the stuff that makes it murky comes from the floor.. when the floor is 5 miles down, it gets pretty clear up top.. We've had 200-300 foot of visibility easily before.. In the boat, yes, you can see sharks down a 100 feet - as long as they're big enough.. the first time I ever jumped in the water with sharks thee wee maybe 30 Black Tips and 10 Lemons circling the boat.. it IS unnerving the first time you jump in, but it gets easier and easier..
I know I've told the story before about our new friends on their first dive in Belize.. dropped their GoPro while getting into the boat.. water there was 120 feet deep, but we were right no a slope where it went from 120 feet to as much as 5000 feet deep - you couldn't see the bottom.. Nobody watched to see where the GoPro landed.. the family who lost it asked for volunteers to go find it.. I jumped at that chance - another free dive? You bet!
So, he and his wife and me and my wife went looking for it.. we split up into two groups: girls and guys.. then us guys went our own way to cover more ground.. not particularly smart being at 120 feet deep alone.. if something were to go wrong, you'd be toast.. Nobody would see you, nobody would know..
As I'm searching at 120 feet for the GoPro - I didn't ever find it, but I did find a fishing pole and a couple of other things - I just looked up and looked up to WHERE I actually was.. I could see the ocean floor at 120 feet and I could easily see the ocean surface 120 feet up.. I could probably see 300 feet ahead of me - at least.. nobody else was in sight, the boat was gone.. it was just me in this HUGE and humbling expanse of open ocean.. I was SO insignificant to the overall picture.. it was definitely a life-altering moment for me..
We never did find the GoPro.. its still there.. I scoured the area, so I'm pretty certain it went over the edge into the 5000 foot deep area, where it will stay for either eternity or until someone with a remote operating vehicle finds it by accident..
Friendship is like peeing your pants.. Everybody can see it, but only you can feel the warmth..