I've got a 175w MH set up. It's two ballasts and two pendents. Your tank isn't very deep so 175's would work good IMO. When I had these over my tank I was growing SPS within the top half of my tank (which is 30" deep). I've been planning on cleaning out the basement and posting some equipment I have kicking around so if you're interested PM me and I'll find this lighting which is in that mess somewhere.
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