SPS dark spot disease? Any cures

[bct15]

I think two or three of my acros might have dark spot disease. They have areas that are greyish/brownish/purple on them and it almost looks grafted as there is a distinct border or separation between the dark areas and good colored areas. Does anybody have experience with this acro issue and a way to combat it? Do I need to frag the infected areas off? I tried fragging one of the corals that had it a few months back and the spots came back in new areas. The dark areas are in parts that get good flow and light as well as parts of corals that get low flow and light so I don't think it is a flow or lighting issue. I did notice one spots on the tip of a branch of my PC rainbow a few weeks ago that is now gone...

 

[bct15]

Anybody?

 

[bct15]

The pictures are zoomed in to show the gray branches and separation between color and grey spots. The first pic is the first coral to show it and it's the small frag in the middle, the second pic the coral has been in my tank for over two years an just started showing this a couple months ago. It started as a couple small spots and has spread to about 50% of the mini colony. Flesh is still there and will polyp out occasionally but the flesh looks dried out and colorless. Here is a little bit about dark spot disease, I've been reading journal articles about since yesterday.

Though only recently described as dark-spots disease (DSD), discolored spots or markings in the tissue of several massive reef-building corals from the western Atlantic have been noted for many years, but not studied. Dark-spots disease was first reported from Colombia during the late 1990s, but the condition appears to be widespread in the Florida Keys and throughout the wider Caribbean (Gil-Agudelo and Garzón-Ferreira, 2001).

The affected areas appear as dark purple, gray or brown patches of discolored tissue, circular or irregular in shape, that are scattered on the surface of a colony, or at the colony’s margin. The discolored tissue increases in size and radiates outward as the area first affected dies. Darkened polyps often are depressed and appear smaller in size than normal polyps (Bruckner, 2001). DSD is most commonly observed on massive starlet coral (Siderastrea siderea) and blushing star coral (Stephanocoenia intersepta), but this condition also affects Montastraea annularis (species complex) (Bruckner, 2001).

The coral in the second pic has been in my tank for almost two years and this just started a couple months ago. Below is my parameters.

Temp 78.8 (apex controlled)
Alk 7.8
Cal 410
Mag 1320
Nitrates ~0
Phosphates ~ .02 but haven't tested in a couple months

Flow is from 3 mp40's with two on back wall in NT mode and one on side wall in reefcrest.

Tank mates are
Yellow tang
Powder blue
Yellow belly regal
Radiant wrasse
Melanarus wrasse
Flame wrasse
Hooded wrasse
Occelaris clown pair
Royal gramma
Bangaii cardinal
Lyretail anthias

 

[Zagreus]

What ever happened here?