Sunburned liverock?! Is this an issue?

[newreefer_59]

Been reefimg for almost a full year now. My 150 gallom tank is established and all LPS/SPS/fish seem to be doing well. All tests are within range as well. Question is my rock that is most exposed to the light seems to be 'washed out' or 'sunburnt'. The attached photo is hard to see but gives an idea of what I am saying. As for lighting, I am using 3 actinics on for 11 hours a day and 3 white lights (46" T5 HO 54w 10,000K Ocean Sun) on for 7 hours. The T5 bulbs are ~ 6" off the water and the white lights are new (two months). Any suggestions?