Volumetric Lighting problem

I did a tutorial here: https://www.youtube.com/watch?v=yq0y8J59GJs My ocean scene comes out too dark. The author of the tutorial said to reduce the density in the World volume and increase the strength of the emission plane. But if I make the scene lighter like he said, I can’t see the gobo rays. Can someone tell me what to do to make the scene lighter but also keep the gobo rays visible?

http://i1130.photobucket.com/albums/m539/Blanco111/HEKP1_zpsaa1836d3.png

Blend File: http://www.pasteall.org/blend/31504

Idk, i feel there are True Lies out there.
World is supposed to end at Infinity, right? And if there is something inside World, even in small amounts, how that would react to the infinite bright lamp positioned at infinity? My attempts (as are yours) show that there is infinite darkness as an output :D.
Make Cube to be your Universe and there is hope then that some close Spotlight will get through Something which you set inside to be a Matter of this Cube.
Since render process for the Volume is mostly waiting game on HW available here check this Theory of Conspiration on your end:
http://www.pasteall.org/blend/31506

If I do as you say (using your edited version of my blend file), the light on the ocean floor is too bright.

http://i1130.photobucket.com/albums/m539/Blanco111/help2_zpscb321500.png

There are a lot of knobs in Blender… Is this any better? Same file:



Plane with Voronoi texture drives 2 Transparent shaders - tweak as needed. Scene panel has Color management - enable and adjust Curves or exposition. Material for seabed. This is to name some.