If you are using PC or T5 actinics, make sure they are true actinics and not the blue bulbs. The difference is the spectrum. The blue bulbs are 460 nm, true actinic 03 is 420 nm. 420 nm is what gives you good color development in SPS. The XM 10K also has a large 420 nm peak. That's why I like it. Even though it is a white bulb, it still puts out a lot of blue and purple color.
Carl, the 6 ft. VHO bulbs are 160 watts, not 140. Are you going to use 5 ft. bulbs instead?
Gary
125 SPS, 75 gal. LPS/softie reef, 9 gal. Nano