stuck on lights. What should I get?

I got a 155 gallon bow front and I am stuck on what lights I would need/ want. I definitely want to get leds and plan to grow coral. The cover for my tank is sectioned off in 3 22" sections. Should I get 3 smaller units to cover each section, out should I get a 4 foot unit? I have been looking at reef breeders photon series. Would the 48" be enough for my tank? Or should I get 3 16" ones? I was also looking at aqua illumination 52s but dint know if one of these would be capable of doing my tank. It is 6 foot long, 2 foot wide, and 2 foot deep. The tank came with a 48" green element fixture but heard it is not good for coral. I am new to salt water and really need some advice before I spend all this money. Let me know what you guys think. Thank you