Odd behavior in Cory catfish

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biofish

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Hey guys!

One of my Cory catfish has been acting a wee bit odd these last couple days. I donā€™t think itā€™s anything to worry about, but just making sure.

I donā€™t know what type of Cory catfish he is, and heā€™s the only one of that type. This particular tank (a 29 gallon) was set up before I knew that different colors of Cory catfish were actually entirely different species. So this tank has about 7 Cory catfish but theyā€™re all different types. They all snuggle with each other at night in the back right corner of the tank so I figured they like each other at least a wee bit. The one Iā€™m asking about is named Ziggy and heā€™s got a bent spine, but Iā€™ve had all 7 of the cories in here for over a year and this is the the first time Iā€™m seeing the behavior.

Anyway: the behavior is just that heā€™s treading water. Like. Heā€™s spending a lot of time just swimming in place in the middle of the tank, most of the time staring out of the glass but not always. My cories sometimes swim slowly across the tank and but never the dead stop swimming in place, I didnā€™t even know that was possible.
CADCA5D4-C0B4-4C40-994D-38D5C118BF2B.jpeg

Like. Heā€™s just chilling there. Wiggling but not actually swimming anywhere. He looks perfectly fine, so thereā€™s no weird white spots, ripped fins, bumps, inability to swim upright, etc. just the behavior.
 
Looks like a "regular" bronze cory, female at that if I'm sizing it up correctly

I've got a mixed cory gang too, I've got 2 pairs of bronze, 2 albino bronze, and 2 salt and pepper. Same boat as you, I didn't know they prefer company of their own class, but they all bunch up together most of the time and they are OK, although I will add more of each variety once I upgrade to a bigger tank.

To your question:
Has there been any recent change to your setup? New fish, plants, decor? Anytning removed?
Any changes in the water? How often and how much do you change? Any changes in the food you feed them all?

Assuming your water params are where they should be (when was the last time you tested) I'd say the fish might be just a bit stressed, either due to lack of company from same-variety or something else, just like us one might assume they'll have a few downer days without persistent effects once it passes.

Does it do anything else? "glass surfing" is another telltale sign of issues with cories, from what I've learned here in the forum.
 
Looks like a "regular" bronze cory, female at that if I'm sizing it up correctly

I've got a mixed cory gang too, I've got 2 pairs of bronze, 2 albino bronze, and 2 salt and pepper. Same boat as you, I didn't know they prefer company of their own class, but they all bunch up together most of the time and they are OK, although I will add more of each variety once I upgrade to a bigger tank.

To your question:
Has there been any recent change to your setup? New fish, plants, decor? Anytning removed?
Any changes in the water? How often and how much do you change? Any changes in the food you feed them all?

Assuming your water params are where they should be (when was the last time you tested) I'd say the fish might be just a bit stressed, either due to lack of company from same-variety or something else, just like us one might assume they'll have a few downer days without persistent effects once it passes.

Does it do anything else? "glass surfing" is another telltale sign of issues with cories, from what I've learned here in the forum.
Ohhh! Iā€™ve never been able to gender them before! But I hope sheā€™s a lady!! That would be so neat! And she does resemble a copper Cory.
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She finally moved when I sprinkled some food in. But she returned to just slowly swimming around the middle of the tank. So not a dead sit still but still pretty slow.

As for changes: the only thing Iā€™ve done recently was a 80% water change a few days ago. I try to change the water 50% every couple weeks but I didnā€™t have time to because I had to go somewhere out of state itā€™s been closer to a month since the last change so thatā€™s why I did such a heavy big change. I havenā€™t changed anything else! I havenā€™t tested the water lately but all the fish look healthy. I have guppies in the tank and typically when something is off in the water, the guppies start acting weird.
 
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Hereā€™s her other side. You can really see the spine bend here.
 
@DoubleDutch is the expert here on cories. He'll be able to give a more knowledgeable opinion.
AFAIK females cories are all absolute units compared to males, in my case they're nearly twice as big.

I'd say you need to test your water, I can't think of anything else that could be bothering your fish, and tbh I've seen some of mine have a similar reaction (seldom) after a big water change. I tested my tap water the other day, to my dismay the pH had gone way higher than it used to be, and I'm now reducing the weekly water change volume and even considering adding chemicals just to force it down because it's gone from a stable 7 range to close to 8 (or higher on my other 2 tanks which don't have as many plants in them) pain in the ass really when the water company changes parameters suddenly
 
I tested my tap water the other day, to my dismay the pH had gone way higher than it used to be, and I'm now reducing the weekly water change volume and even considering adding chemicals just to force it down because it's gone from a stable 7 range to close to 8 (or higher on my other 2 tanks which don't have as many plants in them) pain in the ass really when the water company changes parameters suddenly
Oh goodness that HORRIBLE. Iā€™ll go get my water test just in case šŸ˜¶šŸ˜¶
 
View attachment 161477
Hereā€™s her other side. You can really see the spine bend here.
It is indeed a C.aeneus (green type) that doesn't look okay (does it have its barbells).
The cruising in midwater often isn't a good sign and In my experiences they often don't live for long. Don't know what exactly is causing it but I think it to be a bacterial issue. I also doubt there can be done anything against it in this stage.
 
It is indeed a C.aeneus (green type) that doesn't look okay (does it have its barbells).
The cruising in midwater often isn't a good sign and In my experiences they often don't live for long. Don't know what exactly is causing it but I think it to be a bacterial issue. I also doubt there can be done anything against it in this stage.

Is it really a C.aeneus? Look at the colour of the dorsal, and the pic of it next to the proper bronze. I don't know the species, and maybe the deformity is throwing me off, but the colours and head shape don't look right for aeneus
 
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Her whiskers Seem a bit smallā€¦. sheā€™s currently combing the sand for food.
 
She's not looing brilliant I'm afraid- I have two bronze cories with similar deformities, one very similarly shaped to yours. Have stayed much smaller than a healthy adult cory. Where did you get your cories from?

Bear in mind that with her shape being squashed up in that way, that the internal organs are undoubtedly affected, and it's very likely that they will be more vulnerable to other illnesses, and is likely to have a shortened lifespan. All you can do is give them the best quality of life as you can for as long as you can. If the water quality is good, other cories and fish seem well, and there are no other symptoms, then you may never know what's affecting her, sadly.

If you can post photos of the other cories you have, someone will be able to ID them I'm sure.
 
Apologies for double post, but looked at photos again, and think that might be excess mucus on her sides on one of those pics, but I'm not great at telling if it is - hopefully @Colin_T can help.
 
Thanks for the heads up! Iā€™ve had a couple deformed fish; and yeah they typically donā€™t live as long unfortunately and it greatly hinders their growing rate. (I have a guppy thatā€™s almost 8 months old but still in my guppy fry tank because their bad back has just kept them that small and theyā€™ve been surpassed by numerous batches of fry) I bought this Cory about a year and 2 months ago I wanna say, and I honestly didnā€™t realize she had a bad back until I put her in my QT tank. Her coloring is better in person than in the pictures (slight algae build up hehe) which made it hard to get good pictures. Iā€™ll clean the glass a bit to see if I can get some better shots.
 
It is an extreme deformed fish. I still think it is a green C.aeneus derived from crossbred C.aeneus x C.venezuelanus (then also called C.aeneus). That's how it's got a red/brown finnage. Another option is a deformed C.venezuelanus but the colors are a bit of / unrecognisable.
I have had a deformed C.venezuelanus btw.
It was more red than this one and lived a short life cause of its deformaty.
 
I think it is most likely a Brochis (Short bodied) in not great condition. What is the pH extra of this tank.
 

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