QT tank "mystery"

[michael_in_nc]

I recently transferred some fish from DT to deal with Ich. No major outbreak on the fish transferred but was sure it was present. Fish all died in QT within a few days. I was checking params:

Temp - 80
Salinity - 1.024
NH3 - 0
Nitrate - 25ppm

Nitrate was a little high, but shouldn't cause such a quick reaction. QT has been running for awhile and is cycled. In fact, there is significant algae growth (brown) on the glass.

Now the more interesting part, the glass is suddenly very clean over this time frame. All brown algae is gone and tank is sparkling clean?

Any thoughts? More info I could provide?

Thanks!

 

[MrTuskfish]

Nitrate at that level won't bother fish at all....nobody really knows if nitrate even bothers fish at any level (commonly seen in the hobby, cma).
How did you treat these fish and are you sure it was ich? Just from the timeline; I think velvet (oodinium) is a real possibility. Velvet is a similar parasite; but much deadlier and faster. I'd Google both 'marine ich" & "marine velvet" (include images)and see if velvet is the culprit.

 

[Triton_Z]

I assume you did not have an opportunity to treat the tank with any medications? What was the sure sign of Ich infestation you observed on the fish? Spots, heavy breathing, sheen, lethargy?

Maybe the infestation had already run too long untreated.

 

[michael_in_nc]

Tank was not treated yet. Just moved them over. I really only had one fish showing significant issues at the point that I started moving the fish over. A powder blue tang which was not moved. There were three fish moved to QT ( coral beauty, bangaii cardinal, & Desjardini sailfin ). The sailfin had some mild signs of ich.

This is unfortunately my second round of ich battling. I don't know for sure it was ich, but based on what I've seen it looked like ich. PBT had the most pronounced symptoms. He had the fine 'salt' spots all over him. His eyes were cloudy. He lived for a couple of weeks in this state. I thought he was going to be fine and I would get him moved, but I was trying to figure out how to get him out of my tank (250G reef with lots of rock). He never seemed to eat well and swimming became more erratic with the symptoms.

Any thoughts on the sudden disappearance of the brown algae? QT only has strip lights on it. The algae had been there for awhile and the tank was cycled.

QT is still running. I have a yellow eye tang still in the DT and would like to move him as he is showing signs for awhile now too, but I don't want to make it worse if something is wrong with QT?

 

[michael_in_nc]

Thanks guys, for the inputs!

 

[MrTuskfish]

IMO & IME; many deaths that are blamed on ich are really velvet. Again, this sounds like velvet; or possibly something toxic in the tank. How did the fish look just before they died? If you have ich or velvet in your DT; you have to treat all fish, showing signs or not. The parasite is in the tank. The DT will have to remain fishless for 10-12 weeks to get rid of ich; less if its velvet. I'd read all the ich stickies at the top of the disease forum and research velvet. An understanding of the parasites life-cycle is vital info. No matter what parasite you have; if you don't QT all your fish, let your tank go fishless, and use a QT on all new fish---you'll never have a parasite-free tank.

 

[Triton_Z]

I don't have a good explanation relating the fish deaths and the algae disappearance other than something toxic to all life in the QT tank or coincidence. The PBT symptoms sound like the ich infestation along with some secondary infections (cloudy eye) persisted untreated too long. It's difficult in a large reef tank removing fish.

If you are not running carbon on the QT, I'd run some to remove any possible unknown compounds in the water and maybe even perform a WC. Whether to sterilize and restart the cycle on the QT tank is tough call. I probably would be inclined to do.

If you pulled the infected tang from your DT and have any remaining fish in your DT, you're best next step is to fallow the DT with no fish. It's no fun.

 

[Triton_Z]

Michael,

I'm sorry. I misread your post about the PBT staying in your DT and the others were transferred. What fish do you have remaining in your DT?

 

[michael_in_nc]

I have read the stickies in this forum, but have been mostly focusing on ich. I'll go back and give the velvet one another read. It seemed like everything turned south very rapidly (matter of a couple days), which is what sounds more like velvet.

Right now QT is empty but still up and running. The DT is actually two tanks plumbed together. A 75G & a 250G. All fish in 75G are out, but still have 3 fish in the 250G. They are a Kole Tang & 2 green chromis. The Kole swims into my trap all the time, so I think I can get him. The chromis I'm really dreading...

I was trying to get everything out (fish) to let DT (both tanks) go fallow for the 10+ weeks. The QT issue slowed down my plan.

So, how's this for a plan. Run carbon in the QT, and do a 75% or so water change. Re-read the velvet thread for the best course of action if that is the culprit in DT. Move Kole / Chromis over to the QT and see if I can treat them for the ich / velvet. Leave the DT fallow for at least 10 weeks.

I've been trying to do a QT process, but it obviously wasn't good enough last round. I only did 1 week observation, 2 weeks Cupramine, 1 week observation, so 4 weeks total. Going to need to re-evaluate my process and also make sure I didn't have any cross contamination from any misc equipment. I don't think I did, but I'm going to tighten that process up as well.

Let me know if you have any other suggestions!

 

[michael_in_nc]

I have read the stickies in this forum, but have been mostly focusing on ich. I'll go back and give the velvet one another read. It seemed like everything turned south very rapidly (matter of a couple days), which is what sounds more like velvet.

Right now QT is empty but still up and running. The DT is actually two tanks plumbed together. A 75G & a 250G. All fish in 75G are out, but still have 3 fish in the 250G. They are a Kole Tang & 2 green chromis. The Kole swims into my trap all the time, so I think I can get him. The chromis I'm really dreading...

I was trying to get everything out (fish) to let DT (both tanks) go fallow for the 10+ weeks. The QT issue slowed down my plan.

So, how's this for a plan. Run carbon in the QT, and do a 75% or so water change. Re-read the velvet thread for the best course of action if that is the culprit in DT. Move Kole / Chromis over to the QT and see if I can treat them for the ich / velvet. Leave the DT fallow for at least 10 weeks.

I've been trying to do a QT process, but it obviously wasn't good enough last round. I only did 1 week observation, 2 weeks Cupramine, 1 week observation, so 4 weeks total. Going to need to re-evaluate my process and also make sure I didn't have any cross contamination from any misc equipment. I don't think I did, but I'm going to tighten that process up as well.

Let me know if you have any other suggestions!