What killed this angelfish in QT?

[alexytman]

This angelfish was going through QT. I let him eat for 4 days. I notice it pecking but didn't eat that much. Afterwards I ramped up copper over 4 days to therapeutic without any erratic behavior, it was always hiding in the PVC. Later I found it in a arched position with heavy breathing. I did a quick 5min freshwater dip but didn't notice anything falling off. Gills were a bit red and stomach bit pinched but seen skinnier. Some discoloration on sides and white fluff under fin that doesn't blow off in FW. Never did meds for internal parasite so is that the cause? White fluff also seen near the butt.

 

[Jay Hemdal]

This angelfish was going through QT. I let him eat for 4 days. I notice it pecking but didn't eat that much. Afterwards I ramped up copper over 4 days to therapeutic without any erratic behavior, it was always hiding in the PVC. Later I found it in a arched position with heavy breathing. I did a quick 5min freshwater dip but didn't notice anything falling off. Gills were a bit red and stomach bit pinched but seen skinnier. Some discoloration on sides and white fluff under fin that doesn't blow off in FW. Never did meds for internal parasite so is that the cause? White fluff also seen near the butt.

What type of copper did you use?
What was the test kit?

Red gills are good. The pinched belly is a concern, the fish is very thin, and these don't have a lot of food reserves.

Jay

 

[Timfish]

I've had enough angels (and other fish) start eating with in hours of adding it to QT I'd think it had a problem before I got it.