I would think that you could get by with a 2 bulb T5 normal output as well. I know that on my 20gal high, I was able to grow sps coral with a 2 bulb normal output T5 by Aqueon. If I remember correctly they are pretty reasonably priced.
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"Listen to some of these guys talk, and it's like they were born from their momma's belly with a fishkeeping encyclopedia in one hand and an API kit in the other" (unrevealed).