You could use the hydroponic fixtures...you might have to modify the reflectors some if you want them to fit inside a canopy. You'll want to use metal halide. The HPS bulbs aren't available in the color you'll need. The largest size commonly used in aquariums is 400w. If your tank is at least 24" deep, these should work for you. You'll want to find bulbs that are 6500k or higher. 6500 will give you a yellowish light...may have a hint of green. 8800-10,000k will be a blue/white light. 12,000k is similar with a little more blue. 20,000k has a lot more blue. I think you'll find that the correct bulbs cost nearly as much as the fixtures.
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