You can get rid of colors and change the image in PS, but you should start off with learning from the image and applying it to future UW shots.

Quick tips - not from a pro UW phtographer, but I have some experience...

- Get an external flash for your camera.
- Find out what the focus range is for the lens and then...
- Get closer to your subject(s). Then when you think you are close enough, get closer. (within the focal range)
- Don't aim down when shooting, unless doing macro work with a flash.

That may help you with future images.