Optimum Lighting @ 20"

[Kelpie]

I would like to read the opinions and experiences you have had with lighting 20" deep aquaria. I have a 150W aquaspacelight, (w/electronic ballast and HQI bulb) and I'm wanting to put it over a 20" cube but I'm not sure if it will provide enough light at the bottom of the tank. Would it be good for softies at the bottom and hard corals nearer the top then?

 

I realize there is a very large contingent out there who thinks we should blast our tanks with as much light as possible but I don't think that is always best.

 

I've looked into replacing the 150W ballast with a 250W ballast but they are too large to fit in this fixture. Yeah, I know I could probably run a remote ballast and I may.