Best approach for a corydoras quarantine

[Beastije]

Back to my corydoras. Not sure what exactly happened, but since last week my corydoras started behaving more strangely. The juveniles have been in the tank for almost three weeks now and like 6 of the older corydoras started hanging at the surface areas. One sits on a filter sponge, two in anubias leaves, one in Cryptocoryne leaves right under the surface, one would hang out near the surface glass surfing alone. Some sit down on substrate with the juveniles in places where they not always sat before.
I started feeding less due to the tetra issue but still, interesting behavior development .
They also don't scare away that easily from these places as they do from the bottom.

 

[DoubleDutch]

Back to my corydoras. Not sure what exactly happened, but since last week my corydoras started behaving more strangely. The juveniles have been in the tank for almost three weeks now and like 6 of the older corydoras started hanging at the surface areas. One sits on a filter sponge, two in anubias leaves, one in Cryptocoryne leaves right under the surface, one would hang out near the surface glass surfing alone. Some sit down on substrate with the juveniles in places where they not always sat before.
I started feeding less due to the tetra issue but still, interesting behavior development .
They also don't scare away that easily from these places as they do from the bottom.

They might be hungry. What was it again why you cut feeding ?

 

[Byron]

In addition to what DD asked above, when you post about possible problems always give us the water conditions (ammonia, nitrite, nitrate) so we know. The parameters are very soft and acidic, assuming this to be the case that is no issue. But what is the temperature?

 

[Beastije]

I dont think it is a particular problem yet. I fed in the morning half a cube of frozen cyclops and two days before fluval bug bites. Their bellies are not sunken, barbs are not damaged, no discoloration, no sluggishness.

I cut the feeding cause my embers are too fat and 'exploded'



Temp is 26C and i did a water change two days ago, usual way.

 

[DoubleDutch]

I dont think it is a particular problem yet. I fed in the morning half a cube of frozen cyclops and two days before fluval bug bites. Their bellies are not sunken, barbs are not damaged, no discoloration, no sluggishness.

I cut the feeding cause my embers are too fat and 'exploded'



Temp is 26C and i did a water change two days ago, usual way.

The fact that they might be hungry and in search for food (what Corys do a long period of the day) doesn't mean they have sunken bellies, colorloss, dameged barbells.

Hungry isn't the same as being underfed or malnourished.

 

[Byron]

And temperature at 26C is a tad warm for any cory species, I would look into lowering it to 24-25C. I know this is only one or two degrees, but to a fish which is endothermic this is very significant. Water temperature the fish lives in drives the fish's physiology and metabolism. When kept warmer than necessary it increases the fish's efforts to maintain its functions. A temporary increase is manageable, but not long-term.

 

[Beastije]

That I can do. I fed them in the evening since you scared me, they are still hanging around on the leaves and the filter, but not as many
Will see today, will do an extra water change over the weekend, just in case.

 

[DoubleDutch]

That I can do. I fed them in the evening since you scared me, they are still hanging around on the leaves and the filter, but not as many
Will see today, will do an extra water change over the weekend, just in case.

Scared you ? Aren't we trying to explain certain behaviour. As said hungry doesn't mean you're mistreating fish or you're a bad fishkeeper. This forum is meand to come to a general consensus what possibly is happening. No more and no less. To do so members give there ideas and opinions, which could be incorrect as well.

My Corys (peppered mostly) scavage the whole tank when they are hungry ( they always are).

 

[Beastije]

I have lost two corydoras in the past three days. All from the older batch. No visible signs of anything, no fun rot, no barbel erosion, no red botch, no swollen gills, no spots, no nothing. They didn't even go paler, they went a bit darker. Both were those that hung around on the plant near the surface.
I did the usual water changes no adding to chemistry, all tests are as should be, filter is running.
I am suspecting parasites as those could have been what killed the tetra too. Makes me very sad

 

[DoubleDutch]

Grrrrr that sucks. Could you place some pics of the remaining ones ?

 

[Beastije]

Will take other pictures later but i have no idea

 

[GaryE]

I'm in week 3 of QT for my Corydoras cf incolicana. 3 more weeks and they'll be in a community. I have 5 weeks to go on my brevirostris, CW 123 and concolor. It's really hard to be patient, but I have learned my lesson, more than once. I was finally able to move my trilineatus into their longer term home though.

This is kind of a return to Corys for me, after a few years with just my Scleromystax barbatus, and my all female C armatus. Those armoured bodies are very cool, but they sure can hide a lot. I am keeping them in isolation from other fish until I feel confident all is well. I've actually decided that my C pygmaeus can stay in their QT for good. I've scaped it and let them run - if past experience holds, they'll breed.

@Beastije - you are having unfortunate luck. That amandae Cory mix is not working well. There is always the danger of things getting past QT periods.

 

[Beastije]

I am getting really worried now and am considering maybe borrowing an UV lamp, if it were bacterial, to help treat it?

 

[GaryE]

If it is bacterial, then you have very few options. Which bacteria? Gram positive, gram negative? If you can define it, what meds are available in your country? Or is it viral? Did it come via the problems with the tetras, or did it come with the Corys and a short quarantine?

It appears to me like you have a need to provide the best possible conditions in terms of tank maintenance, and after that, the difficult task of watching how it plays out.

@DoubleDutch may be able to help more with available meds under European rules - there I don't know. I imagine if he could, that would already have been offered as info.

 

[DoubleDutch]

If it is bacterial, then you have very few options. Which bacteria? Gram positive, gram negative? If you can define it, what meds are available in your country? Or is it viral? Did it come via the problems with the tetras, or did it come with the Corys and a short quarantine?

It appears to me like you have a need to provide the best possible conditions in terms of tank maintenance, and after that, the difficult task of watching how it plays out.

@DoubleDutch may be able to help more with available meds under European rules - there I don't know. I imagine if he could, that would already have been offered as info.

Only thing is that also in Europe we only can treat diseases if we know what we're facing.
Most parasites (internal and external) show symptoms. As asked I like to see.some pics of the remaining fish.