J4Life
Premium Member
My lights are about 10 inches off the top of the water and I have egg-crate covering the top of my tank. My tank depth is 21 inches however I have placed that orange/peach yuma mid way up directly under my 250 watt, single-end, 10K XM bulb. The best suggestion I can make is to start low and work your way up however I haven't been a good follower of that philosophy myself. I don't know how much brighter DE bulbs are than mine but I am certain they're still not as bright as our sun on an Ocean reef.
Hope that helps some.
Hope that helps some.