Possible case of marine velvet

[dnas17]

Heres the story, about a month ago I purchased a bicolor angelfish. At first we had some trouble getting him to eat but he eventually started eating flakes, pellets and frozen food everything was perfect. A few days ago however, he stopped eating. At first I thought that he may just not be very hungry but this morning I found him hiding in a cave gasping laying at the bottom. I knew this was his final stand and a few hours later he was dead. I found him with a sugary looking coating on the back of his body and what looked like a bruise around his gills and face. As of right now I just performed a water change. None of the other 4 fish (2 clowns, longnose hawk and a six line wrasse) show any signs of sickness and are all happily eating and swimming around the tank. Any advice on what my next move should be?

[robt18]

Bicolour Angels are pretty famous for being caught via cyanide fishing.... of course cyanide toxicity is a huge side effect of this and often doesn't present until the new owner has had the fish for some time. I'm not exactly sure of the symptoms but it seems like a pretty good fit based on really basic knowledge and info.

[Greatwhite]

Fish also have a way of sensing when other fish are "not well" and will go on the attack.  If your angel was ill, the other fish could be responsible for the bruises around its face and gills.

I had an Anthias who was a little loopy from the start, and he ended up getting pummeled to death by my clowns.  It's always the fish you least expect...

[dnas17]

Well I don't know too much about cyanide poisoning but I would take just about anything over marine velvet, the good news is everyone else appears to be doing great. Swimming and eating no signs of sickness or weakness, but yeah when I found the fish he had almost a perfect circle near the back of his body of what looked like white powder. I would also be surprised if the bruising was caused by my other fish since they are significantly smaller than the angel and are also generally very friendly.