With kessil , I have found to get a decent spread you have to have the light as high off the water line as wide as you want to cover. I have a A160 hung 16 inches above a bio cube 14 to get the coverage I was looking for without "NUKING" everything in the middle. I would go A360 for sure, you will need that extra penetrating power( when mounted high above the tank for coverage) . With proper planning and rockwork you should be fine. Your tank dimensions are pushing the limits of any single led light to cover. Depending on your budget the new gen 4 Radions look promising . They seem to have better spread then previous generations for a single unit. If cost is an issue the 360 can be added to at a later time , either this tank when you stock it enough and your inhabitants demand more light or as we all do.... upgraded tank later.