Just going to throw my 2 cents in this one, since i had it rough when i was cycling.
If i may make a suggestion, i would advise to cycle the tank with the table shrimp method. I just think it is cleaner, and quicker for that matter. Instead of using the decaying matter off of live rock to cycle the tank. I cycled my tank with live rock, and thought it would have been a good idea, but IMO, i was dead wrong. I had so much dirt and grime in my tank, that you could not even see the white sand that i had. And that was all stuff coming off of the rocks. Another thing was that since i had 75lbs of live rock, there was tons of things on it that were dying off from the beginning of the cycle. That was when my ammonia levels went off the chart, way past 10ppm. At 8ppm beneficial bacteria begins to die off.. so in other words, i had so much ammonia, that my cycle could not continue. So that was agonizing. Four 75% water changes later, and i had only dropped it down to 5ppm, but that was a good place for the cycle to begin. So.. out of all this, i would say use the shrimp method, or use the pure ammonia method, and then just get cured live rock to put in your tank when it is cycled. This way, you'll have really nice rock, and your tank won't shoot off of the ammonia readings chart. And restating what the others have said, there is no question that you need a skimmer. A tank that large needs to have a skimmer. Also, if you do get fish like tangs, or triggers etc.. they put a real shift on the bioload in your tank, and by that point, you will definitely need/want a skimmer to keep the water clean. Clean water = healthy everything.
I also have 2 Koralia #2's in my 55G and they produce great flow, all throughout the tank. So in your case, maybe a #2 and #3 would be good. A lot of people say to get all of the same kind when it comes to powerheads, but i've yet to see what the big difference is. If i could have gone back to change what i bought, i would have gotten a Koralia 1 and a Koralia 2 because right now, even though my tank gets great flow, i just think it's a little overkill.
The people above gave some great advice, so all these answers should help you to understand what it is you want to do with your tank.
Good Luck and please! Keep us posted!