Velvet

[Jcj0033]

I bought a few new fish about 2 months ago I quarantined them for 3 weeks in
Copper then added them to the tank. They have been in the main display for 2 months without showing any signs of velvet.
Now I’m afraid I have a velvet outbreak !!
The fish are cover in what is either ich or velvet and they are swimming into the Powerheads and hiding !! They are still eating so maybe there is Hope !!
How long can velvet be in a tank without causing an outbreak ?
I would think if it was velvet it would have struck a while ago

 

[Andy Sager]

Sadly, there are parasites with long life cycles and Cryptocaryon and oodinium have an approximate 60 day cycle so QT for 3 weeks may have not been long enough to prevent this occurrence. Copper is only effective for one of the stages of the parasite's reproductive stages.
That all said, and assuming that this is a large aquarium because Tangs get very stressed in smaller aquariums, something has stressed the fish that they succumbed to a parasitic infection. To determine "WHAT was the stress" better, please give us current water parameters including temp, stock, tank size, etc.
Be prepared to remove the fish to a sterile hospital tank to treat as the best med for parasites is copper or copper based and will get absorbed by your coral decorations and kill your inverts.