Light help....

First of all, my tank is odd shaped... 2'W x 1'D x 2'H.  It has been up and healthy for more than a year now with 2 Clowns.  Now I'm going to add soft corals, but my single 24" bulb won't be enough.  I have the opportunity to buy a used Current 4x24, but I'll need some advise on what bulbs to use and what I should set two timers at.

I realize that I'll be increasing heat, so I plan to mount it at least 4" above the water.

Thanks for the help.