If I remember correctly, you have a 20 you are setting up? The most versatile lighting as far being able to keep anything would be metal halide. Whith this though, you would run into some real heat issues in a smaller tank. I would suggest
VHO lighting as this is vesatile and wont create as much of a heat issue. It is also cheaper by far than Metal halide. You might still have some heat issues but this can be fixed with a small fan blowing on the sump water or in the light canopy. The ultimate factor in picking lighting is what you want to keep in the tank. Im sure you can find some great deals online and even better if you are handy woth do-it-yourself stuff.
Im sure others will chime in with more wisdom and info to pass along! HTH
Robert
