To me #1 is best, since there is not so much foreground distracting from the shark.
Actually the amount of water is not more there if I see it right, just less foreground.
In the thumbnail the shark also is bigger, so I'm not sure if Slobodans argument is really valid.
To me the aspect ratio of #1 also emphasizes more the width and less the height of the image and such appears more to stress the "wide ocean" environment and focuses more on the area in front of the shark (possible prey?) than the area below it.