Thanks for sharing; much appreciated!As some of you know I am in business of selling qted fish.
My recommendation for captive bred fish like yellow tangs, hippos, angels etc that are sensitive to copper is to leave them in a sterile tank for 30 days. Then next 2 weeks or so you can do prazi and metro to clean the internal. 45 days later If you don't see any parasites like ich or velvet then you are good.
If you must then do a 1ppm copperpower and over few days bring it to 1.5ppm and that's about it for 14 days.
These fish specially angels are very very sensitive at that small size and age. Any slightly harsh treatment will kill the fish quickly. Just my opinion and experience.
When you say “45 days later If you don't see any parasites like ich or velvet then you are good.”… is that 45 days on top of the 30 day observation + 2 weeks prazi/metro (i.e. total quarantine time of approx. 90 days)?