[Myka]

Since your tank is only 20" wide, but 30" deep (which is a significant depth to light) T5s wouldn't be your best choice. you can get 18" T5s, but the selection of bulbs is very few, and the intensity of the output is quite low. I think you would be much better off looking for a MH light for your tank. Since your tank is 30" deep I would suggest you try to find a 250w MH as they are only a little more money than a 150 or 175w. Since you (probably) won't be supplementing with actinics, try to use a 14-15K bulb for a slight blue tint to make your corals look nicer. This would allow you to keep pretty much any corals, anemones, or clams you may ever want.