it should be under the most flow you have possible, not a direct jet slamming it but rather a nice flow across it, all the polyps should be extended and should notice flow gently swaying them every couple of seconds or so.
It could also be your nitrates as SPS corals aren't as forgiving as softies. I'd move it to some more flow and do a water change. your PH is also a little higher than normal, whats your phosphates running that could be browning them as well.