Fish death mystery

savvyskrill

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Hi everyone, longtime lurker first time poster here. Would love your opinions!

I left my boyfriend in charge of my 15 gal tank while I was gone for a week. During that time, all 3 of the fish died within a day. Clownfish pair and a royal gramma. He unfortunately did not take pictures but said everyone was fine the night before, then he woke up in the morning and the royal gramma was a skeleton (I'm guessing the work of my blood red fire shrimp), the female clown was dead and white at the surface, and the male clown was barely clinging to life down on the sandbed and had "turned white" with what looked like "a sore or a bite" on side of body. He died later that day.

4 soft corals, 2 LPS corals, 5 species of macroalgae, 1 conch, 8 snails, 4 hermit crabs, and the fire shrimp are all completely fine.

Yeah, currently dealing with BOTH dinos and cyano. I already beat dinos once by dosing phosphate and nitrate and adding pods. Now it's back with a vengeance along with cyano, which was a surprise when I returned from my trip.

Could the dino resurgence and/or cyano kill the fish so quickly? Could it have been brook or velvet even though the newest addition was the royal gramma over 3 weeks ago? Overall tank is about 7 months old.

Research here leads me to rule out lack of oxygen. There was no power outage and I have a 357 gph pump with dual random flow, both aimed towards the surface in opposite directions. I also doubt coral toxin since all the corals and inverts are fine. I run carbon with a pouch clipped into the flow from one aio chamber to the next. Using RODI for all top offs.

I only do a 20% water change about once per month in order to keep nitrate/phosphate high for the macros and to keep dinos at bay (until now). Could that be the culprit somehow?

Is a 3-way aggression battle possible? The female clown was a notorious bully, but I don't understand how the male would be last one standing only to die later too.

Parameters:
1.025 salinity
0 ammonia
30 nitrate
0.1 phosphate
8 alkalinity
480 calcium
7.8 to 8 pH

Welcoming your thoughts!

IMG_7859.jpeg
 

Fish Fan

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Sorry to hear about your losses ☹️

Your parameters look good, your inverts you say are fine, and you've ruled out low oxygen, so to me that does sound like a fish disease. Unfortunately, without pics of the ailing fish, I'm not sure anyone could say for sure what may have happened, but we can see if maybe the #fishmedic team has some ideas for you.

I believe that 3 way aggression could have been happening, but you'd expect to still have one triumphant fish in the end, they don't usually all die, but I supposed it's possible 🤪

I do think it's possible that some disease causing organism was in your tank, maybe the Gramma brought it in or it was there already, but then some stress event cause the disease to take hold whereas before the fish were holding it at bay. Of course, that's just my $0.02 🙃

Good luck going forward!
 
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W31Olds

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Not Aggression. More than likely the Gramma brought in some Pathogen. Low Oxygen is also possible but not likely. Is it possible that your Boyfriend turned off a pump by accident?
 

Jay Hemdal

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Hi everyone, longtime lurker first time poster here. Would love your opinions!

I left my boyfriend in charge of my 15 gal tank while I was gone for a week. During that time, all 3 of the fish died within a day. Clownfish pair and a royal gramma. He unfortunately did not take pictures but said everyone was fine the night before, then he woke up in the morning and the royal gramma was a skeleton (I'm guessing the work of my blood red fire shrimp), the female clown was dead and white at the surface, and the male clown was barely clinging to life down on the sandbed and had "turned white" with what looked like "a sore or a bite" on side of body. He died later that day.

4 soft corals, 2 LPS corals, 5 species of macroalgae, 1 conch, 8 snails, 4 hermit crabs, and the fire shrimp are all completely fine.

Yeah, currently dealing with BOTH dinos and cyano. I already beat dinos once by dosing phosphate and nitrate and adding pods. Now it's back with a vengeance along with cyano, which was a surprise when I returned from my trip.

Could the dino resurgence and/or cyano kill the fish so quickly? Could it have been brook or velvet even though the newest addition was the royal gramma over 3 weeks ago? Overall tank is about 7 months old.

Research here leads me to rule out lack of oxygen. There was no power outage and I have a 357 gph pump with dual random flow, both aimed towards the surface in opposite directions. I also doubt coral toxin since all the corals and inverts are fine. I run carbon with a pouch clipped into the flow from one aio chamber to the next. Using RODI for all top offs.

I only do a 20% water change about once per month in order to keep nitrate/phosphate high for the macros and to keep dinos at bay (until now). Could that be the culprit somehow?

Is a 3-way aggression battle possible? The female clown was a notorious bully, but I don't understand how the male would be last one standing only to die later too.

Parameters:
1.025 salinity
0 ammonia
30 nitrate
0.1 phosphate
8 alkalinity
480 calcium
7.8 to 8 pH

Welcoming your thoughts!

IMG_7859.jpeg

This sounds like a gill parasite in the fish. Velvet (Amyloodinium) can cause huge mortality in just a couple of days - especially if the person caring for the fish may miss the "faster breathing" which is often the only symptom.

The 3 week time frame is within the normal range for this disease to show up in new fish.

At this point, you'll need to keep the tank fishless for 60 days.

Going forward, you might consider quarantining your new fish:

 
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savvyskrill

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Thanks, everyone! I didn't know it could take that long for disease/parasites to set in, that must have been it. Was hoping for another reason so I didn't have to go fallow, and that's the last time I'll trust LFS saying they quarantine. Lesson learned 🥲
 

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