It's on the 20 gallon. I have no idea what kind of par I'm getting, but everything looks happy. I have been moving all the LPS to my other tank and making this one a SPS dominate tank.
If I recall correctly, I think you have a mid sized tank. The 18 inch model is newer and has been configured to balance out the channels closer to 50-50, but would probably take a couple for your tank and you would likely have to suspend them. The 32 inch model would probably fit better, but I don't think it has the new layout.