Dying fish -- diagnosis? with pics

[Kinbote]

I've been posting on another forum about the problems I've had with fish dying in my quarantine tank since introducing a batch of sick cardinal tetras (which I immediately returned). I've had 6 deaths of my own fish, rosy tetras and bleeding heart tetras, in the past two weeks.

I'm treating for columnaris, have completed two cycles of Furan-2 and am starting a third, but it's had absolutely no perceivable effect with the fish still steadily dying, so I have to suspect there's another underlying cause.

I'm trying to keep the temperature down to 24C (75F) as recommended for columnaris but with the ambient room temperature it's usually nearer 26 (79F).
Ammonia and nitrite have consistently been reading 0.
The fish aren't eating much and I'm not feeding them much, so I doubt decayed food is a factor, but I've removed most of the gravel in case that was harbouring anything.
I've also added tonic salt in the last couple of days since that's meant to inhibit columnaris's ability to attach to fish.

But if it is columnaris (or saprolegnia) I'd have expected it to respond to Furan-2, and it wouldn't make sense that this all started after contact with some sick cardinal tetras.

My last bleeding heart that died was a lot more symptomatic than the current ones, but I didn't get a picture unfortunately. It had the characteristic columnaris whitened saddle ring around its dorsal fin and some fuzzy white patches on its side.

I don't see anything on the rosy other than some internal whitening around its stomach, which looks vaguely like NTD, which would fit my suspicion that they might have NTD and only have columnaris as a more obvious, but secondary, infection.



The bleeding heart has a big patch of fuzz on its mouth and some more on its left pectoral fin and tail.



And here's a pic of one of the sick cardinals that seemed to start it all about 2 weeks ago.



Hope someone can suggest something. Pretty depressing so far.

 

[Lupin]

Do you have a bigger resolution of the cardinal pic?

Your second pic indicates classic case of fungal infection. It's very rare to happen but it looks like one here. That might explain the alleged resistance to Furan-2. Do you have access to Maroxy? I'd give that a shot.

How much salt was dosed?

I really think that if this all happened since the introduction of the cardinals, then you need to bleach the tank. Bleach the other equipments as well that you might use to other tanks. Did you disinfect the tank after returning the cardinals?

 

[Kinbote]

Do you have a bigger resolution of the cardinal pic?

Unfortunately I don't, but the back third of it had turned yellowish-white where the stripe used to be. Another cardinal from the same batch had the same problem but moreso. Looks a lot like the pictures of neon tetra disease that I've seen.

Your second pic indicates classic case of fungal infection. It's very rare to happen but it looks like one here. That might explain the alleged resistance to Furan-2. Do you have access to Maroxy? I'd give that a shot.

I agree; I think it looks like saprolegnia, but from what I've read that should also respond to Furan-2.

The fish were all very healthy before the cardinals arrived, and columnaris and saprolegnia are both opportunistic and more likely to be secondary infections, which is why I'm wondering whether NTD is the underlying cause, and that it's just not as visually obvious in bleeding hearts and rosies as it is in neons and cardinals. If their immune systems are shot because of that, that would also explain the lack of success with Furan-2, I guess.

How much salt was dosed?

Two tablespoons per 10 gallons, as directed.

I really think that if this all happened since the introduction of the cardinals, then you need to bleach the tank. Bleach the other equipments as well that you might use to other tanks. Did you disinfect the tank after returning the cardinals?

I agree. If it had been nothing but columnaris, the Furan-2 should have cleaned it up and cleaned the filter, but if it's NTD or something else fungal, the spores are going to be a lot more resistant. Is bleach going to be enough?

 

[Kinbote]

I'll see if I can find Maroxy. I euthanised the last visibly sick fish today (the bleeding heart in the picture), so we'll see how it goes.

 

[Lupin]

The bleach will be enough. Rinse thoroughly after use and let dry.

Trouble is there have been so many antibiotics used for mistaken cases of "fungal" infections that not all antibiotics will work for the true sapro so I thought Maroxy is the best chance we have at this point.

 

[aclockworkorange]

Just a note for anyone else who looks this up, I successfully treated columnaris with kanamycin.

 

[Kinbote]

Re Lupin, no, I didn't disinfect the tank after the cardinals were in it.

Here's the long, boring story:

I'd moved my 15 fish (10 rosy tetras and 5 bleeding hearts) out of my 75 gallon tank and into a 10 gallon quarantine tank while I got my 205 gallon ready to go.

They'd been in there about a week, very healthy, and while I was at a shop I don't usually visit, I saw some cardinal tetras for sale which had been out of stock at my usual place for a while. Stupidly, I decided to get them (11 in total), and while the guy was catching them I stupidly went to look at driftwood. I'd noticed one fish in the shop's tank near death, but didn't think much of it as it's a pretty common sight.

Once they were bagged they were all lying on the bottom and keeping still, and I couldn't see much so didn't bother inspecting them, having never had cardinal tetras before and assuming the store guy knew better than I did anyway. Although when he was ringing up the sale I did notice that he was, well, pretty stoned.

Once I got home and got the fish acclimatised and into my tank it was immediately obvious, first off, that he'd sold me the near dead one that I'd seen rolling around in the tank at the shop. I'd never heard of NTD and didn't really know whether the yellowing towards the back end was just a juvenile colouring variation or what, but at least three of them had it to varying extents and it was fairly obvious that they were unwell. I removed the obviously sick ones immediately but had to leave the others in overnight since the shop had closed and I didn't have anywhere else to put them. Took them back first thing in the morning and got a refund, although they assured me that their fish were fine and the problem must be with my tank. The next day, my own fish started to show symptoms, and over the past two weeks 6 have died, one after another.

Now, it's partly my own stupid fault for not quarantining new fish and not checking them out properly in the store, but I do think that being stoned on the job and selling people fish that are already 90% dead is pretty negligent. I mean, if it had been something that took a week to show signs, then fine, it'd be all my fault. It later turned out that the stoned guy was the co-owner, along with his wife, and seemingly the sole curator of the aquarium section. Lesson learned.

 

[Kinbote]

MarOxy isn't available in my country. I've got some formalin that I bought to sterilise my nets; should I give that a shot? If not, any other alternative to MarOxy?

 

[Lupin]

Maroxy is chloride oxide. Maybe look for other meds accessible that may have the same ingredient in it.

 

[Kinbote]

Maroxy is chloride oxide. Maybe look for other meds accessible that may have the same ingredient in it.

Pretty much all we've got available here is Malachite Green, Formalin, Acriflavine, Methylene Blue, Melafix, Pimafix and Furan-2 which I'm already using without effect.