Deep Tank Lighting Advice Needed

[FishDad2]

I've got a 225 gallon tank that's 72"l x 30"h x 24"d and am using a 72" Hamilton retrofit kit with 3 x 250w MH & 4 x 96w PC bulbs. The tank has been in operation for about 2 years and overall things are going fairly well.

That said, the only significant problem I seem to have now is that the SPS just don't do as well at the lower levels of my tank, but once I bring them up higher, where the light is brighter, they typically perk up. I've added flow and made lots of changes, but it really seems to come down to the light just not being sufficient for such a deep tank.

So, I'm looking for lighting recommendations ... MH wattage and specific fixture recommendations (brand, model, etc.). If I go to 400w will that be enough? The last thing I want is to upgrade and fall short...30" is pretty deep and my bank account has limits!!

One final thing to keep in mind as regards the fixture is that I think I should stay away from the 72" reflector design as is used in my Hamilton. Not that there's anything wrong with it, but my LFS built the tank with a center overflow, which means that the middle MH lamp shines a good portion of its light into the overflow...wasted light. If I move the unit more toward the front of the tank so I'm getting better use of that bulb, then the other 2 lamps are no longer directly above the corals on the reef and their effectiveness is reduced.

I'm thinking that since the center lamp needs to be offset towards the front, I either need 3 separate fixtures independently mounted or a custom built 72" fixture with that center lamp offset to the front.

Thoughts and suggestions are appreciated.