Why did my fish die in quarantine?

[BilboB]

Yesterday was day 12, both fish (yellow tang and kole tang) were swimming and eating just fine. Today, the kole tang is dead and the yellow tang is lying down & breathing hard. Water temp 77 degrees, salinity 1.024, pH 8.2, no ammonia or nitrite detected with the API kit. The lawnmower blenny looks OK. I did an 80% water change and added nitrofurazole, but it's probably too late for the yellow tang.

Any ideas? It's a 20-gallon tank using RODI water and Instant Ocean salt.

 

[StartingATank]

I could be wrong but my only guess is that salinity is a little low, but I don't think that would cause this. Are there any signs of disease? Can you give pics of the two fish?

 

[mfinn]

Were you treating with anything ( copper?)

 

[fish_collector]

Sorry to hear about your fish. There's not enough info to say for certain why your fish died while in QT. We the readers have to take what you tell us as truth because that's all we've got to go on, you say ammonia is 0 so that rules out that. You mentioned your yellow tang is laying down and breathing hard, so I'd say you either have inadequate oxygenation of the water due to lack of surface movement, or you have a case of velvet in the tank. Both would fit the narrative based on the info you provided.

You didn't tell us your experience level, or anything about your QT or what other meds have been administered. But regardless, lack of oxygenation and/or velvet would still be my guess if I had to guess.

 

[Ziggy17]

Things you will have to provide

Medication?
Copper? What kind? What strength?
Prazi? What kind? What strength?
Filtration? What kind?
Photos under white light! Not blue light. short video is better.
Aeration? What kind?
Food being eaten?
Rapid breathing?
Signs of white dots?
Hiding places for the tangs? PVC pipes.

Apologies if I missed something.

 

[W31Olds]

What protocol were you following and what Meds were being used? Don't worry about photos since your Fish have passed but the Blennies behavior is helpful.

 

[Ziggy17]

What protocol were you following and what Meds were being used? Don't worry about photos since your Fish have passed but the Blennies behavior is helpful.

YT is still alive but barely.

 

[BilboB]

It was just a holding tank while my DT cycles. No copper, no meds. Neither fish had signs of disease - no ich, no velvet. The tank has a HOB filter, 2 grapefruit-sized cycled live rocks from my LFS, and 2 air stones set to high. There's also a dish with non-calcareous sand for the blenny to hide in - I washed the sand thoroughly before I set up the tank. The tangs occasionally hid behind the rocks or some plastic plants that came with the tank - I never saw them in the PVC elbows. But they did eat when I gave them some mysis shrimp daily.

I did some water changes earlier (like day 3 and day 7) due to ammonia, but haven't done any changes in the last 5 days because the ammonia levels were always zero. Unfortunately, the yellow tang died since my original post.

 

[fish_collector]

Sorry man. It happens. It’s easy for us to point the blame at this or that, but there’s really too many factors that could have the same result.

I keep bags of rock rubble in the sump of my display tank for use in my QT when I use it. It’s instant and no questioning it when I need it. My reefing buddy sometimes uses a dissolved oxygen test kit for things he does, more or less as a diagnostic tool if he has an issue with a fish. Just another tool in the toolbox to rule out causes.

Again sorry about your tangs.

 

[BilboB]

Sorry man. It happens. It’s easy for us to point the blame at this or that, but there’s really too many factors that could have the same result.

I keep bags of rock rubble in the sump of my display tank for use in my QT when I use it. It’s instant and no questioning it when I need it. My reefing buddy sometimes uses a dissolved oxygen test kit for things he does, more or less as a diagnostic tool if he has an issue with a fish. Just another tool in the toolbox to rule out causes.

Again sorry about your tangs.

Yeah, I'm having bad luck with quarantining. In my other QT, late last year, I tried using BRS' method of 100% water changes every 3 days with no live rock or media. My 3-inch clown tang was fine on day 4 but died early the next morning.

Fortunately, the hospital QT I'm running now - treating a blue hippo tang and an angelfish - seems to be fine. I'm treating with copper, doing ~75% water changes every 2 days, and have Matrix and BioBalls in the tank. It's day 7, so I have 7 days to go.

 

[areefer01]

Not sure it was asked but you mentioned both kole and yellow. Source of purchase of each and was it the same?

Yellow tangs are captive so you either purchased it direct from Biota or though a LFS that did. Kole online or lfs. Kole could be the source of the problem unless both are purchased from the same online/lfs.

 

[Mebbid]

Can't say this is it for sure, but tangs require some type of algae or seaweed in their diet and even though they eat mysis it's not good for them to only have that in their diet. It's believed that the mysis or high protein diet without fiber causes constipation and can cause bowel rupture or other issues. Having seen constipation in tangs I believe it.


Would be weird for it to happen to both fish at the same time, but what else is there to go on?

 

[BilboB]

Can't say this is it for sure, but tangs require some type of algae or seaweed in their diet and even though they eat mysis it's not good for them to only have that in their diet. It's believed that the mysis or high protein diet without fiber causes constipation and can cause bowel rupture or other issues. Having seen constipation in tangs I believe it.


Would be weird for it to happen to both fish at the same time, but what else is there to go on?

Yeah, I probably should have fed them nori instead, or mainly nori with some mysis.

 

[BilboB]

Not sure it was asked but you mentioned both kole and yellow. Source of purchase of each and was it the same?

Yellow tangs are captive so you either purchased it direct from Biota or though a LFS that did. Kole online or lfs. Kole could be the source of the problem unless both are purchased from the same online/lfs.

Yes, the yellow tang was from Biota and the kole tang was from my LFS. Both were fine and eating for 11 days. Maybe nitrates were the problem.

 

[areefer01]

Yes, the yellow tang was from Biota and the kole tang was from my LFS. Both were fine and eating for 11 days. Maybe nitrates were the problem.

Kole is more than likely the source then since it was in the LFS system. If you try this again in the future my suggestion is to separate them. Buying first directly from Biota or similar source that does not touch the supply chain (like a LFS water) can be done differently.

 

[W31Olds]

The Yellow from Biota was probably Clean, however one or both of the other Fish were not. Qt protocol with Copper needs to begin shortly after the Fish arrive and show interest in Food. Your Tangs probably have a Gil Parasite causing problems. Those Biota Yellows are small so you may not be able to save it as Copper will Take time to work. Make sure your Lawnmower is eating as they can be difficult to get through QT because they are Grazers.

 

[mfinn]

Yeah, I'm having bad luck with quarantining. In my other QT, late last year, I tried using BRS' method of 100% water changes every 3 days with no live rock or media. My 3-inch clown tang was fine on day 4 but died early the next morning.

Fortunately, the hospital QT I'm running now - treating a blue hippo tang and an angelfish - seems to be fine. I'm treating with copper, doing ~75% water changes every 2 days, and have Matrix and BioBalls in the tank. It's day 7, so I have 7 days to

@Jay Hemdal

 

[higher99]

Marine velvet? That’s so strange.

 

[Jay Hemdal Verified Community Expert]

It was just a holding tank while my DT cycles. No copper, no meds. Neither fish had signs of disease - no ich, no velvet. The tank has a HOB filter, 2 grapefruit-sized cycled live rocks from my LFS, and 2 air stones set to high. There's also a dish with non-calcareous sand for the blenny to hide in - I washed the sand thoroughly before I set up the tank. The tangs occasionally hid behind the rocks or some plastic plants that came with the tank - I never saw them in the PVC elbows. But they did eat when I gave them some mysis shrimp daily.

I did some water changes earlier (like day 3 and day 7) due to ammonia, but haven't done any changes in the last 5 days because the ammonia levels were always zero. Unfortunately, the yellow tang died since my original post.

I don’t think this is water quality issue (for sure not nitrate) and it isn’t anything dietary.

The description sounds like Amyloodinium, velvet. The early symptoms of that are easily missed.

It isn’t a good idea to hold fish in a QT under purely observational management.

I just updated our quarantine protocol:
https://www.reef2reef.com/threads/current-quarantine-protocol.825055/

 

[MadreeferNJ]

This used to happen to me during the winter. I would wake up and several fish dead overnight with no signs of illness. It seems excessive CO2 in water was the cause. During cold months no open windows or doors so it builds up. I placed an air pump outside a window and ran a long airline hose to the tank for a few hours a day.
This stopped the mystery deaths for me.