Whoh, soooo, some thoughts, you said 90 gallons, they tossed a bunch of info at you, but you need to think, what is going to go into my tank?
Types of coral dictate the lighting... I am not sure your experience, but judging from the questions you're asking, not much (no offense).
I think you should approach this differently, of course every tank is going to evolve as time goes on, but there are things that are standard pat for most tanks.
Sooo, think about your water filtration, first and foremost. You have a reef ready tank. You have a sump/fuge.
Let's talk that first.
Then let's talk biological filtration inside the tank, life rock, sand bed etc. and water circulation.
All that depends on a stocking list.
Once you've addressed those issues, then you can start talking lighting...
Also where are you at? most of the time heat is the issue not cold. Once you start submerging all those pumps, have lighting etc, those are all natural heaters...