problem with green chromis

[Dyncaus]

alright, i wen to feed my tank today and noticed that my green chromis was missing, so i searched around the tank and finally found him sitting on the sand between two pieces of live rock breathing heavily. he will not eat and just stays at the bottom. i took him out and have him in a bucket, just in case whatever he has is contagious, the two clowns and coral beauty all look fine, its just him that looks sick, anyone know what it might be and how to fix it? thanks

[Instar]

Whats new to your tank? Do you have a condylactus anemone? Rapid breathing symptoms can be from all kinds of illnesses and chemical poisoning, even during collection. If you have a long tentacled anemone, chromis naturally dart into staghorn coral branches when they get frightened by something. In the heat of the moment, he could dart into tentacles in just a reflex action and get stung. Stings can kill many small fish.

If its fairly new to your tank, many times the onset is triggered when you acclimate it from the LFS as they keep their water quite diluted. You acclimate too fast and incompletely and open up the gill membranes to infection from osmotic shock as well as the parasites that were not completely irradicated at the LFS or caught at the LFS. It can take a few days to set in good. Once done, its likely not to be undone. Osmotic shock results in as many if not more fish and invert deaths than any disease or chemical, IMO.

[Dyncaus]

i only had the condylactis for 2-3 days, and then i gave it away, the chromis was my most recent fish and has been in my tank for about two weeks now, until now everything has seemed normal.

[kaiser]

If You are going to keep him in the bucket for a while put at least an airstone in there. The extra oxygen may help him recover.

[Dyncaus]

i was searching online and think it might be velvet disease? does anyone know anything about velvet?