You did everything you could to try save your fish. Sometimes even when we do everything right, we still lose fish. So many unknowns: how the fish was collected - cyanide, blasting, etc., shipping trama, diseases exposed to during shipping, etc.
But here's the toughest part. Many collectors, shippers, and LFS are keeping fish at below therapeutic levels of copper to reduce losses and keep the fish looking sellable condition. Copper can be rough on a fish. It is after all poison. And most fish's colors fade from the exposure. So we buy from them and the sub therapeutic level wears off and the disease(s) comes roaring back, often without the visible symptoms because its attacking unseen in the gills. So by the time you finally see external symptoms, its often too late. The internal damage was too great and the fish's immune system has been compromised.
