lighting for 270g

[Mike-fish]

i have 3x400w mh lights on the 175g that maybe shut down in the next few months with the arivall of the 270g . the 175g is 28" deep with the lights 8" off the water. the 270g is 24" deep i plan to have the lights (same as above) 8" off the water as well. otherwise with canopy you get the little window in a big box look. the 270 is 36" wide do you think they will spread far enough out fixture is 12" long? will i have too much light at the sand bed for most corals?