That's a Current USA Orbit 48" 4x96W SunPaq fixture. See
model #1031 here. These are PCs, not MH.
I would think it's not enough for SPS in a 90 gal, but I'm not a lighting guru nor am I trying to raise SPS. Maybe if you put those corals a bit off the bottom it would be fine.
I would get a mix of Actinic and daylight bulbs. Maybe 1 Actinic 420nm, one 50/50 (10K/Actinic), one 10K, and one 6700. Or if you want more blue-white, ditch the 6700 for another 10K.
As far as the moonlights go, I would suspect a faulty switch, blown fuse on this circuit, or corrosion on the wires. I wouldn't expect the moonlights to burn out. If you can get to the wiring, it might be obvious as to what is wrong.
--Chris