Experienced reefer puzzled at fish deaths

[IrezumiHurts]

Many tanks with no disease or symptoms at all have Uronema. The Aquabiomics may say its there - but - its probably in many many many tanks (with no negative consequences)

This is true. But it is also true there are multiple strains of uronema, and it's not entirely understood which ones are truly obligate detritovore/bacterivores, or what conditions must be met for morphologically similar variants to infect fish.

So one aquarists may have a fish death attributable to marinum. Another may have a morphologically similar strain, with no fish deaths. Or you could have someone with marinum with no fish deaths, but maybe that tank doesn't stockprone species. It's not clearly understood what conditions are required to make the leap, but once it happens, it can cause mass wipeouts, and worst of all is most insidious to often not leave a trace beyond a befuddled reefer.

As i said in the first post, when all the other common sense blocks are basically checked, it's often that one thing that's left on the table. But i don't think uronema is some sort of red herring, personally i think it's the worst and least understood fish disease in the hobby

 

[IrezumiHurts]

I think you are probably right. This is a very strange and uncomfortable territory for me. You can prob tell by my handle but I’m a human physician. So I’m used to having ideas of what’s causing a disease in a patient and being able to test to confirm my suspicion. So having no testing for these diseases sucks!! And yes. It seems like one by one I’m having a fish die. Acting fine. And then I notice they’re gone and find their body being eaten by a crab or coral banded. There is definitely no prodromal period where I notice they’re acting sick. And if there is it’s hours long. And I work like a dog lately so il not home staring at the tank constantly to notice subtle changes.

Just wait till you research what you need to do to actually a) rid your tank of it if you have it and b) prophylactically QT for it. There is no FALLOW period for it because it can feed on detritus and bacteria. It's no wonder many just decide to live with it or choose to avoid prone species. As mentioned by other members sometimes you get lucky and the problem just "goes away" over time even if the pathogen itself does not. A lot of anecdotal support is there for older systems being more resilient. But like your situation there are others who found they just up and have an outbreak years down the road, if that was the true cause of your first issue. And it can be incredibly hard to keep it out of the tank, due to challenges of treating it internally vs externally. It's generally accepted once it manifests internally is not treatable so a fish can essentially become a Trojan horse but most of that can be mitigated by a simple 2 week observation period after all QT protocols have been followed for the fissures to present if they are going to.

People get worked up over ich and velvet. Those are childs play.

 

[Jay Hemdal]

Hey Jay thanks for the reply. So I will rewind a little bit. When I had the old tank I had a mass fish die off event too which lead me to leave the tank alone for probably 8 months. In those 8 months i had two clowns and a hawkfish which were totally fine and thriving as was the rest of the coral. Once I upgraded to the reefer I introduced probably 15 fish over 2 months. So i had a weird very similar die off event in the old tank too pre the new fish addition. I posted above I am now seeing a cardinal who is clearly moribund floating around being blown around by the wavemakers. No sores no skin issues, maybe a few ratty looking fins but nothing is obviously wrong with the fish externally anyway. ***, I feel like a terrible fish owner.

One symptom of flukes is that the fish tend to look tattered and “shop worn”. It’s tough to describe, but I’m still leaning in that direction.