SPS, MH and bulb distance

[Aquattro]

Originally Posted by reefknot

I have got 2 x 400W mogel base MH set at 17 " above water

That seems a bit high. I run mine about 6" off the water, thinking of moving them up a couple inches, mostly to eliminate blasting the top corals, and giving myself a bit more room to work in tank without burning myself.
Keep us posted on SPS growth and color at that height!