It might just be a bad picture, but the belly on that Regal Angel appears "gray" in color. That's indicative of an Indo-Pacific Regal Angel rather than an Indian Ocean/Red Sea specimen. You indicated earlier that you bought an "Indian Ocean Regal." The Indian Ocean/Red Sea Regals have a bright orange belly and they do MUCH better in captivity than their Indo-Pacific counterparts. The IndianOcean/Red Sea Regals are also much more expensive than Indo-Paciifc fish. If that fish was sold to you as a Red Sea or Indian Ocean fish, I'd look into it. If you get a better picture, I'd be able to tell for sure.
As for the marks and not eating, I'd wait a few more days before I became very concerned. The fact that it took any prepared food is a very good sign. The next few days will be very telling. It should be exploring the aquarium and start eating more and more prepared food at each feeding. If it does not steadily improve, then you probably have a bad fish.
By the way, for anyone else reading this, I know that some people have claimed to have kept Indo-Pacific Regal Angels alive in captivity, but I've NEVER seen it done for any real length of time. I would never buy or recommend that anyone buy an Indo-Pacific Regal angel. I'd even be in favor of banning the collection of these fish. OTOH, I've seen many Indian Ocean/Red Sea Regals live long lives in aquariums. One of my Regal Angels died recently after 8 years in my aquarium. I have another that's 5 years old and going strong.
Greg
