The first picture I was a little sceptical on but this one sure looks like it. It kills clowns very quick though(mine were dead in 2 days). I now keep formalin on hand for this reason as the day I discovered it no LFS in NB were open or they didn't have it. The next day they were dead. Luckily they were in my QT instead of my DT but I was shocked how fast they died.
This is why I am wondering if it isn't Marine Velvet as yours seemed to live a little longer. Copper is very useful if it is. I also say this because Brook(also known as Clownfish Disease) is rarily found on other species( I do remember someone posting a pic of a yellow tang with it though so it isn't impossible of course). Just thought I would throw it out there so you could research that and see what you think.
I wondered if it was marine velvet, but my other clown is doing well in QT on Formalin (well, 3 days of formalin and now he's just in QT acting what I'd consider normal). I'm not sure is Formalin and Malachite Green is effective on velvet? The clown that survived no longer has splotchy/sloughing skin as shown above in that picture, although that is the one that died and my other clown didn't seem AS "sick" by the time I got the QT going.
My wrasse has a cloudy eye and a splotch on his side. I'm trying to catch him and my chromis (and firefish if he's still alive) to move them all to QT for bulk treatment and QT until 8+ weeks pass in my DT for brook to die off. I've read brooklynella is HIGHLY contagious to every fish once exposed to it.