Step 34
Set the dodge tool to 30 % exposure in highlight mode (600 pixels brush) and highlight the ocean floor.

Step 35
Make a new layer above the background (title doesn’t matter).

Step 36
Now, using a 23 % opaque brush and color #BE7709, make the ocean floor appear to disappear into the distance. This will require some layering, with the least amount of layers in the distance, and them building (becoming more opaque) as they approach the bottom of the screen.

Step 37
Now, using the dodge tool set to 30%, layer and swirl across the background to create an illuminated water effect.

Step 38
Now, going back to the coral layers, swipe the dodge tool back and forth across the sea weed and coral, to make it look like there is spattered light falling on them.

Step 39
Lastly, make a large shaft of light filtering down on the background layer, and then use the dodge tool to make it appear to be falling on the “ocean floor” layer, as well as the other coral layers.
