Although your photo is good, I can't discern a whole lot of detail about the coral in question. Still, based on its shape, my first guess would be that it is a gorgonian. Do you know if it is from the Caribbean or the Pacific? In the states, we rarely get Pacific gorgonians; I suspect hard corals bring exporters more money.
Some of the tips of the gorg look discolored -- is it losing any flesh? Most will shed their outer layer on occassion (to rid themselves of algae), but when the gorg's flesh starts to fall off and the horn-like branch base shows through, then you know you are starting to have problems. They can bounce back from that, however. It is usually recommened that you trim off any decaying parts to healthy flesh.
There are times that my gorgs will have areas where the polyps will not extend, despite the rest of the gorg's polyps being open, so I wouldn't worry about that. Especially new gorgs, they will close their polyps when any new thing brushes by them, until they get use to the environment. Now, one of mine will stay open even when my goby perches on it and my seahorse hitches on it.
From what I have read, gorgonians vary in the amount of flow that they prefer. There are some species that actually occur more on sanding bottoms where the current is slow, such as the Pseudopterogorgia sp. (often called "feathers" or "plumes.") Others will tolerate slower moving waters, but are found where the currents are at least moderate. The species that have a branching shape similar to yours are listed as needing moderate to high laminar flow perpendicular to the coral.
You may want to try to feed a phytoplanton together with some cyclops/cyclopeeze to see if you get a feeding response. Many people report that their gorgs will capture larger food like frozen brine shrimp, but Borneman stated that the gorgs usually release these without ingesting them.
