Shooting under water takes special gear and special considerations for lighting and composition. Here are a few samples.
Same camera same lights but the one on the right looks better because the shadow cast by the lights is not visible.
A couple of photos taken in shallow water. Natural light is always best.
Adding more sound to your original footage can make your video come alive. Play the video to see the difference.
Adding a known shape into your video can define the scale of your main attraction.