Ballast Question

[dirtyreefer]

Which would be better for a 36" tank? Two ice cap 175W MH ballasts or one 400W TAR ballast?

The thing that's nice about the icecaps are that I can switch the bulbs if I don't like the one I am currently using, but they are a weaker wattage.

The thing that's nice about the TAR is the high wattage, and I would plan to use one 10000K Ushio bulb.

I plan to supplement both with NO actinics.

Any suggestions?