I run a 6 bulb T5HO fixture on my 75 gallon and have plenty of SPS. As Kevin said, keep your high light demanding species closer to the top. There are a few SPS you'll probably not be able to keep, but for the most part, you'll find a lot that you can keep happy. Whenever I'm in Kevin's, before buying, I ask him...lol. He is, afterall, the SPS Guru!!