Depends on the fixture and the mounting height. I wouls think you will need 6-8 Kessil A360's for a tank that size. Have you looked at the Aquatic Life LED/T5 hybrid system? You could get that fixture and use 4 Kessil A360's and have the best of both worlds.
https://www.bulkreefsupply.com/60-hy...atic-life.html