Weird Corydoras syndrome?

[aquanatix]

Hey guys, just wanna find out if anyone here has noticed their corys behaving weirdly? In my case, i realize that my corys often have a habit of just going into "a state of trance". Individual pieces will often just stop after or during feeding time and then fall into a daze. Often they'll lie motionless, on their sides or like mine...often belly up! Many a time have i come home to find "dead" corys and start getting pissed off at myself for not maintaining water parameters in my tank! Only minutes later do i find that they're all alive after trying to remove them out with my tweezer. The weird thing is that out of my cory population of pandas,hastatus etc...ONLY my pygmaeus exhibit this strange behaviour after almost months of observation. After recovering,these individual fishes will then seek out the others and resume normal foraging activities. Been trying to answer my doubt for quite sometime now so hopefully someone here can share some insight on this strange "phenomenon"?

[Freshman]

Hi aquanatix,
Can you provide more info on your tank water's parameters/tank size/no. of fishes inside?
What are you feeding them with?
IMO it is not advisable to use any tweezer to 'remove' or hold them. You might accidentally injured them. A net is more suitable in case they again suddenly returned back to life.
Are there any major changes to the tank/water parameters before this weird behavior appears?
More description of the c.pygmaeus will help also.

[aquanatix]

Its a standard 2FT heavily planted tank...2bps Co2 dosing and 55watt lightings 6hours a day. Fauna will include 6 brigatte,11 galaxy,my corys and some shrimps. Due to large fauna population, aeration is provided when lights off with weekly water changes coupled with the support of a Hydor prime cannister. Ph of water is kept constant at around 6.5~7 the last time i checked.
To address concerns,tweezer was not used predominantly to 'remove' or hold my corys. It was a case of simply assuming that the cory was already 'dead' hence the need for removal.Referring to my story above,its a one time thing only? My shrimps even crowd around my supposedly dead cory to scavenge over remains.Otherwise tweezers are usually used to gently prod my corys to check if they're really dead.
No addition of flora or fauna was made whatsoever in the months of observation. This weird behavior just happens! It only happens with c.pygmaeus? Not only a particular one but the entire school with no particular order. All other fauna and flora are fine, even the corys themselves are fine after going into a daze which is why its puzzling.
I've probably got over the stage where I'm worried,it's more like curiosity on finding out just why my corys are showing such strange behavior. Any helpful insights? Or has any cory keeper here noticed similar symptoms?

[lyh]

One of my albino cory exhibit the same kind of behaviour, lying on its side motionless like it is dead. I can't figure out what causes it to behave this way too and out of the 10 or 11 cories I bought only this one behave this way. Initially I thought because it is an albino cory it must have something to do with its genes but now that you mentioned I think it is the cory itself.

[aquanatix]

Hope more cory enthusiasts will come forward to share their views.
I believe i'm not the only one? Just that in my case ALL my corys from a single species exhibit the same behaviour!
Been doing some reading up but nothing conclusive yet...anyone else?

[Freshman]

could it be Fish tuberculosis?

[Quixotic]

Can't tell for sure, but it does not seem to be a problem for the period when one of my Cories who is showing this behaviour. Oddly, only one of my entire gang, a C. aeneus started lying on one side some six months ago.

I didn't observe any other issues aside from the new behaviour, it is more than 4 years old, eating well and as active as before. Unfortunately, shame that it has passsed on recently after getting into an accident in the tank.

[aquanatix]

Sorry for your loss Quixotic...hope it isn't some fish TB as mentioned by Freshman!
Anyway,guess this will go down as one of the WTH? situations that'll never be resolved?
All in all,i'm just happy my corys are all doing ok. I'll definitely have to learn to try turning a blind eye on the behavior and not get irritated!

[Quixotic]

Thanks, *ahem* died of an accident, not disease related.

[Freshman]

All in all,i'm just happy my corys are all doing ok. I'll definitely have to learn to try turning a blind eye on the behavior and not get irritated!

I guess only an autopsy can tell what actually gone wrong with that dead cory.

Anyway, I think it is good habit to get curious & irritated by unusual fish behavior. Because it will then create a learning opportunity for youself and us(when you post in forum).

[aquanatix]

Oh well,don't seem to be learning much...so i'll just give in and what the heck?
Like i said,so long they're alive that's fine with me!
Seems like there are more pleco lovers as compared to corys here,maybe should start a purely cory thread to gather all cory enthusiasts together maybe can find out more?

[corydora]

i love corys...will always prefer them to plecos. i did notice this behaviour in my pandas. they will swim around and suddenly stop, letting themselves be carried and swayed a bit by the current. then they will continue. sometimes they will roll over on their sides.

[DazzleDiscus]

My cories sometimes show this behavior- although I only see them do it around lunch time, usually I'm not home around lunch though. When I do see them, (they are C. Trilineatus) about two or three will perform this "resting", then get up and return to the others. I have had these guys for a long time and haven't had major problems with them. I've heard from other cory keepers that their cories exhibit this strange behavior as well. I highly doubt it is fish TB. I keep them well fed with flake, frozen, freeze dried, and occationally live foods, so I don't think mine do it because of some nutrient difficiency. Anyway... my two cents worth. I've never seen mine roll over completely- but my Pygmeaus do sit their in a "dazed" fasion. Course they also blink- and that behavior is normal.

[luenny]

I have 5 different species of cories but never seen any of them resting on their side before. I do see my cories resting but never seen them resting on their side or belly up before. Mine will stop on a leaf or rock or driftwood or even the ground to rest but always in upright position.

[DazzleDiscus]

yeah- last time saw one of my fish upside down it was dead! ...ahem. that was a while ago... and there was only a carcas left.

[chooz]

I observed the same behaviour in one of my c. paleatus. Just this one out of the whole group. Lying on its side, slightly curled, or lean on its back vertically against the glass wall. Been doing that for a while. But when it comes to feeding time, it regains its activeness. Really puzzled by its behaviour.

[aquanatix]

Nice to know(albeit unfortunate) that someone here experiencing same problems!
After so long i'm still getting the same thing!Guess it'll never go away?

Anyway as mentioned,so long it doesn't die it should be ok i suppose?

[chooz]

Bad news. My weird corys died yesterday, after 3 weeks of getting the symptom. I think it has something to do with the tubifex worms that I started feeding to the fish on a once a week basis 3 or 4 weeks ago. Another of the corys seems to be getting the symptom..... The symptoms do sound like fish tb.

Thankfully, all the tetras in the tank are ok. I have stopped on the tubifex meal already and did a major water change.

So sad... I really like the corys, they are so full of character

[DazzleDiscus]

That they are. Sorry to hear of your loss- perhaps the changes will help.

[luenny]

So sad to hear your loss. If you're feeding live tubifex, I'd advice you against it. Unless they come from a very clean source, chances are they carry parasites. Anyway, hope that your other cories recover soon.