Setting up my 150 gallon tank....question re: live rock placement and flow

[newreefer_59]

My 5' X 2 ' X 2' tank has been newly setup for about 6 weeks now with about 150 lbs of live rock. I have, at present, 2 6055 Tunze power heads running on opposite ends. I do have a controller as well - which I have not set upyet, but will soon.

The lights are T5 (6 X 48") and I only keep 2 on as they are very bright as it is. Firstly, is that ok, and how high should the light be over the water surface?

Question: is there a definitive answer how I should place the live rock as well as the power heads to ensure the proper flow, etc. How many powerheads should I have and where?.......and should I have 4 that connect to the controller. At moment, there is little flow behind the rock and alot of crap is settling back there.

I plan to have primarily an LPS coral and fish environment

Many thanks