And how much money are you willing to spend?

A pair of MH will run you $400 new if you buy the inexpensive retrofit kit.

I run 2 250watt Ushio 10000K and 2 96watt PC actinic on my 58 breeder tank and I am very happy with it. I am going to try Colorvue 20000K to see if I like the color better. Either way the light is excellent for SPS. I could get by with less but would not want to.

If you are not keeping SPS than you could use less light.