mysterious PBT qt death

[Fishfinder]

I recently had an outbreak of velvet in my tank. Either got through my previous QT practice (which is now stricter) or got brought in on a coral or invert. So all fish came out of my tank into a 40gal Qt. Fish in qt are sailfin tang, powder brown tang, 2 lyretail anthias, mandarin. So the only fish that had visible symptoms was the PBT he looked very covered but no trouble with breathing. They went through 30 days of copper. All symptoms gone. All fish looked great. I removed the copper with water changes and cuprisorb. They have been in unmedicated water now for 6-7 days. I woke up to the PBT dead. I'm not sure what happened. All other fish look great, the PBT looked great yesterday. I dont if he had an internal infection that I couldnt see. He was eating like normal. Ammonia alert badge looks good. Should I have treated with antibiotics prophylactically?

 

[Maritimer]

Hard to say, about the antibiotics... Some infections are internal, and show few symptoms externally.

I've seen velvet that shows no physical symptoms externally, but is only discernable by the fish's behavior - was the powderblue hiding excessively, or swimming into the flow of a powerhead or filter? How was his breathing - normal or rapid?

~Bruce, saddened by your loss . . .

 

[Humblefish]

Do you still have the body? Drop it in FW (tap is fine) to check for flukes. You should see little white specks in the water after 3-5 mins.

 

[Fishfinder]

He was not acting out of the norm. He always hides when im in the room. I dont have him. Do you suspect flukes?

 

[Humblefish]

I dont have him. Do you suspect flukes?

Not necessarily, but I've gotten into the habit of always giving a deceased fish a FW dip (to check for flukes) just in case. Nothing to lose, ya know? The only time I don't is if I'm planning to do a necropsy, in which case I will take gill scrapes to check for flukes.

 

[Fishfinder]

I understand. We'll see if anything else shows symptoms. Its just odd, he died well after treatment

 

[aykwm]

Might be stress as i noticed pbt stress from almost anything, although its still fish dependent and each fish is different, it might also be internal infections, and so on. It happens in this hobby that sometimes fish die suddenly without any visible symtpoms. Hopefully the rest of the fish are healthy.

 

[Humblefish]

^^ Just to add: We only know about (and can treat) what we see wrong externally with a fish. (A few exceptions: White stringy poop if the fish has intestinal worms, gas bubble protruding outward from the swim bladder, a "lump" protruding outward in a different area could be an internal infection or growth.)

Then think about all the things that can & do go wrong inside our own bodies, but fish don't have the benefit of an X-ray or MRI. So in a way, we're only able to treat about 1/2 of what can go wrong with them. Most of what goes wrong on the inside we just chalk up to a "mystery death". Unless you do a necropsy to look for clues.