Disease? Bacteria? Never determined what happended.

[rldcpa]

I had a nicely populated mixed reef tank when all of a sudden a couple of fish had trouble breathing as they were swimming by the vent. I lost 1 out of 5 tangs, the clowns and quite a few Chromis, overall close to 1/2 my fish of which they were all small except for 1 tang which died a few days before the others got sick. I never figured out for sure what it was but thought it could have been some bacteria, but not ick as nothing ever showed on the fish. It may have been velvet but could never see anything and never could get anything to confirm it. All the fish that did die, died within a week.

Now its 3 months later and I have had no issues except that ever since the event, the 4 Chromis that did survive have always been at the top and are inactive. They eat some but not much else and generally 1 is in each of the 4 corners.

Could they have been damaged in some way or are they still sick? All the other fish are extremely healthy.

One tang had the disease or bacterial infection (as he was always by the vent during the event) but got better within a few days and is now perfect.

So, what is the deal with the surviving Chromis? And as much as I want to add fish, I am afraid to do so as long as I do not know why the Chromis are still acting this way.

Also, I did get a good size UV unit about a month ago and am running that which has made the water very clear and hopefully if the water has/had some free swimming disease or bacteria, it would reduce the amount exposed to the fish.

I never treated the fish as I was never sure what I had, and I hated to treat healthy fish. Also, it would have destroyed my tank and corals if I had to try to get all the fish out as they would have hid in the rock and I would have had to practically disassemble my live rock.

Looking for any insight as to what happened or is wrong with the Chromis so I can decide what to do next if anything.

 

[rldcpa]

Update - I bought and installed a 80 watt Emperor UV for various reasons and to see what it would do to the inactive Chromis. The effects of the UV was that my water went from fairly clear to crystal clear. It is incredible how clear a UV will make your tank.

After about 30-45 days of running the UV, the Chromis got better. They are more active, eating better and swim around a lot more.

I believe the UV has killed either bacteria or some disease that was affecting the smaller fish like the Chromis. I am not saying that a UV can kill all diseases in a tank, but it will kill all disease that go through the unit.

So the UV looks like it is a great addition to a reef aquarium and it has not hurt my corals at all as they are growing nicely.

 

[tylersarah]

My fish acted strange when recovering from flukes, actually I'm not certain they're cured fully. Heavy breathing was my #1 symptom, lost 70% of fish, then they acted unusual, slow at catching food, spastic, lethargic etc. As I continued with Formalin treatment these symptoms slowly lessened and now I believe they may be disease free. My thought is that you're managing a disease with the UV, possibly flukes and it may be still in the tank.

 

[rldcpa]

That is certainly possible, but that was one of the main reasons I got the UV. As long as the flukes, bacteria, or velvet never gets the upper hand again, then I can live with that. Of course it would be nice to believe or know that the parasite is gone, but that is highly unlikely.

I wish I knew for sure what it was, but I never saw anything on the fish and I have had no symptoms since. I never treated the fish as I did not want to destroy my tank trying to catch all the fish and the other issue is how do you treat 15 fish (4 being tangs) in a hospital tank....too many large fish. Also, I could not see putting the fish and tank through all that stress when the remaining fish were totally healthy.

The next test will be when I add a few fish in the next couple of months. To complete my tank I want 2 clowns, a female McClosker's wrasse, a pearly goby, and a bunch of different schooling Chromis (these accounted for almost all the losses from the event).

 

[tylersarah]

Please keep us updated, I'll be following along. I went the tear the tank apart route and will be returning the survivors to the display Nov 20th.

 

[rldcpa]

I thought about going that route but we decided against it as the survivors were all healthy other than the under the weather Chromis.

But if you look at my tank today, everything looks great and everyone is healthy.

Adding a couple of new fish will be the test. I have added some coral and snails but nothing else yet.

 

[tylersarah]

Go slow...

 

[rldcpa]

I plan on taking it slow but so far I praise the effect of a properly sized UV.