I'm in the final stages of planning my new reef tank which will be 300cm x 70cm (front to back) x 90cm deep. I was going to use another LED manufacturer but after reading up on people's impressions of the LX7206 I'm considering switching (plus I recently installed a Profilux 4 and KHD and am a happy customer!).

The tank will be predominantly (if not only) SPS. I would like to mount the lights to the ceiling above the tank to avoid having to have a rack system to move them out of the way for maintenance in the tank. The distance from the top of the tank to the ceiling is about 60cm and probably 65cm to the water surface...

How many of these lights would I need to get very good coverage over the entire tank? and in what configuration (perpendicular or parallel to the length of the tank)?

And any idea whether I can still get 200 to 300-400 PAR in the tank given the height of the lights and the depth of the tank? Today I'm running LEDs that are 29cm over the water level of a 50cm deep tank and I have the LEDs dialled down to about 50% and getting good PAR and growth (I ran them at higher % at first and burned corals).