Lighting

[noah]

I am looking to purchase a dual metal halide full hood setup and am confused as to what to get I am not as worried about the initial investment just the efficiency. I wondered if a dual 150W HQI setup by aquline would be enough for my 75G. Are the HQI 150s brighter than normal 150s I am trying to keep the power usage down as much as possible. I would like to keep some high light corals like clams and maybe sps would this be possible with 150W or am i stuck going 250W.
TIA

[bill-e]

If it were me, I'd go for the 250w. Can you get away with 150w? Yes. The difference in electric cost will be far outweighed by the upgrade cost to 250w or 400w at a later date...an upgrade that there's an 80% probability you'll want to make.

[Doug1]

The 150 HQI is roughly the equiv of 175 MH, but its still only 300 watts on a good size tank. I know its comparing apples and oranges but I have 440w VHO on a 75 soft coral tank and want to add another bulb to each ballast for around 600 watts. Nice thing is I only have to add a pair of end caps to each ballast rather than scrappin it and buying something new.
Just as a reference the light level in a MH lit tank approximates the light level on a tropic reef about an hour after sunrise, FWIW