First sump

[Travis L. Stevens]

It's not really a matter of watts per gallon. And when dealing with larger tanks, it couldn't be much further from the truth. Light intensity is what makes the biggest difference. Their ability to penetrate the water. PCs cop out to almost nothing at about 20", VHOs about 24-36", T5 24"-36", and MH vary on their wattage. 175w will penetrate a lot less than a 400w. The 400w can effectively keep low light stuff all the way to about 36"- 48". If you wanted to do an SPS tank out of it, I would go all 400w and possibly add either a 1000w or a couple extra 400w for intense lighting.

If you wanted to do something like a Soft Coral only tank, you could get away with doing a bunch of NO bulbs or big PCs if you really wanted to.

 

[parshmar]

You should honestly think about T5's for that. They put off more light per watt. Don't worry about watts per gallon, especially when comparing differnt kinds of lights (MH, T5, VHO, etc). Some lamps are more efficient, meaning 100 watts from light "A" is brighter than 100 watts from light "B".

With T5's, you will be able to keep just about any kind of LPS I can think of, any soft coral and a lot of different SPS corals. I'm not sure how tall that tank is but SPS could do well if placed in the middle and up. I think you could keep LPS on the bottom if you wanted. T5's are bright. In Europe, there are tanks bigger than this using only T5's and only keeping SPS. Use an Ice Cap ballast to "overdrive" them, meaning, brighter lights and shorter lifespan (maybe 3-4 months shorter at most). Triad ballasts will burn the bulbs to spec. Add a few fans in the canopy (false canopy) and the bulbs will last a very long time. If you go with T5's, make sure you use a good parabolic reflector (looks like a "W"). Otherwise, you aren't getting the real benefit of T5's. Good luck with it.