Lost a PBT, not sure why

[tripper]

I bought a powder brown tang on Saturday and acclimated him to my QT. He was looking great in the LFS and ate brine when i was there. Once I had him in QT I put some nori on a clip but he did not touch it. I figured he was just adjusting to the tank. I came home from work yesterday and he was breathing heavily, laying against a piece of PVC pipe. It also looked like his skin was peeling off or he was shedding, very strange. All my parameters were good, but I did a 20% water change last night just to see if that would help too. This morning he was dead.

Any idea what could have happened to kill him so quickly? I've had very good luck with fish recently and this LFS always has great quality. I just can't figure out what could have killed him so fast. Please let me know if you have any ideas.

tripper

Originally Posted by tripper

It also looked like his skin was peeling off or he was shedding, very strange.

Brooklynella or velvet most likely. How was the ammonia and nitrite?

Cheers
Steve

[tripper]

Ammonia and nitrite were both at zero. Nitrate is at 10ppm.

Is it the change of environment that brought that on? It's just very confusing to me how the fish could look perfectly healthy at the store (it had been there over a week) and looked perfect when I first acclimated, then after 1 full day was sick and dead.

So what should I do with my QT tank now? It is empty but I want to make sure I don't infect another fish if I want to try again. Do I need to treat the tank?

Thanks

tripper

It's hard to be sure on why the fatality was so quick but in general terms, stress and an enclosed (untreated) environment for the most part. Most LFS keep a certain level of copper in their systems so some fish actually give the appearance of being healthy when indeed the problems only being slowed down. Keep in mind with velvet, the treatment only affects the free swimming dinospore so while on the fish, it is unaffected by treatments and can easily be carried into your QT. I am by no means advocating treating prophylactically, just a possible explaination. I do not think anything you could have done would have been successful anyway. I would speak with the LFS about a store credit though. This fish was sold to you sick.

Since it's near impossible to be sure what the tang actually died from, it's best to tear down the QT, clean well and re-establish before getting a new addition.

Cheers
Steve