Help identify possible marine disease

[Blu3s94]

5 days ago I added 4 fish to a 55 gallon quarantine tank that I purchased from LFS.
Scopus tang
Kole tang
clownfish
Lavender tang

Yesterday was day 4 and I started cupramine at .25. To my surprise today my kole tang and lavender are breathing heavily and not eating. The Scopus and clown are ok. I did a large water change and added carbon thinking they are sensitive to cupramine... well the cupramine is nearly gone... (.01) and they are still breathing heavily and not swimming much at all or eating.

No prime was added and the quarantine was well cycled 2 months prior. Have a seachem alert ammonia badge so those can be ruled out. The only thing I can think of is velvet... Should I fw dip? I have never dealt with anything but ich.

I was planning on Prophylactic treating with cupramine and prazipro. That is why copper was added in the first place. Fish were eating and looked healthy before starting cupramine on day 4.

Sent from my SM-G950U using Tapatalk

 

[Blu3s94]

I will add that I did my best to examine for any external parasite with a flashlight and didn't see anything. Just very rapid gill movement on the 2 tangs, not swimming, and not eating.

Sent from my SM-G950U using Tapatalk

 

[Sk8r]

Oxygenation may be an issue: these fish consume oxygen bigtime and are long-range swimmers. My best advice is once you are sure you have all cupramine out, connect your skimmer to the dt if you have to set it in mid-tank---if there turns out to be disease, you can clean and "Prime" it to clean out. A high-level skimmer produces a lot of oxygen, and I'd run it and just let it discharge water back into the tank. Copper depresses appetite, among other problems. I'm not a big fan of prophylactic copper, for precisely this reason. RUn carbon to get the stuff out, and simultaneously hype the oxygen levels via skimmer. Once it goes down, it's like being sealed in a bank vault...gets bad real fast.