30 Gallon Tank Cory Cat stuck on side?

This afternoon after changing around 25% of the week after I found one of my Panda Cory catfish on his side. He swims in a corkscrew motion and is slightly smaller than the other two. The tank has 3 green cories, 3 peppercorns and 3 pandas. No other fish is showing anything similar.

Water parameters:
pH: 7.5
Ammonia: 0ppm
Nitrite: <25ppm
Nitrate: 0 ppm
Temp: 74.6

*Cup is only for picture purpose. He is in a net breeder that is sold at PetSmart but is not good for picture purposes

 

Oh no... he does not look too good Your nitrites are 25ppm, or 0.25ppm? There's a huge difference. Is the tank cycled? How large is the tank?
Usually for corydoras there should be one big school, maybe two if your tank size permits, but I find that one large group brings out their characteristics. How long did you have these fish? (Or the one that is struggling)

 

Sorry, I meant that at <0.25ppm. the tank is a 30 gallon tank. The pandas and peppercorns I got in December of 2019. So they are around 5 months. The green corydora have been in the tank for about a month. The tank is cycled and has been running for roughly 6 months now. Up until the most recent water change my levels were the same as the first post but nitrites were at 0ppm

 

Sorry about your fish. I do not have any answers for you but I have had a similar problem. I will share my story. Maybe you will find some clues.

I bought 8 Pandas the end of January. 4 died in the first few days. 3 more died since then. Several of them showed similar difficulties to yours before they died. One lived for a few weeks like that. I few times I thought he was dead and then he would swim away.

I have been perplexed and wondering if I am doing something wrong. The ones that died in the first few days may have been weak to begin with. But I do not understand the others.

Most people thought some kind of bacterial infection. I did not try treating with an antibiotic.

One of the theories was substrate. Too abrasive and or food got down into the substrate and forced them to damage their barbels getting down to the food. Or maybe starving because they could not get to the food. Some said my substrate would be okay if the food was bigger and would sit on top. Others said they need to be on sand. When I was down to three I moved them to sand. Might just be the picture but yours look like they have short stubby barbels like mine. What kind of substrate are they on? If you google pictures of Cories you will find they should have long whisker like barbels.

Some said barbel erosion is a water quality issue. I am good with water changes. Ammonia and Nitrites always zero. Nitrate below 20, usually below 10 ppm. But I do not vacuum real heavy so maybe some bad bacteria in substrate combined with irritation due to rough gravel allowed a bacterial infection to develop.

Some said Panda are a weak variety of Corydoras. I heard that from multiple sources. Don’t know if that is a myth or not. But I am planning another school of Corydoras for another tank and they will not be Pandas.

Sorry I do not have any suggestions for you. I will follow your thread with interest. I hope your fish recovers.

 

Aww I’m so sorry! We bought 6 sterbas and had 2 die off pretty quickly, sadly it started with them laying on their side. Awfully sad. They were the two smallest of the group, and the remaining 4 have done great and have grown pretty fast, I know they should have a larger group, but at this point we are fully stocked and I worry about introducing new sterbas to the group since the 4 we have are pretty tight knit. Nothing but luck to you!

 

Sad update: the little guy did not make it. He seemed to get better for a while, then rapidly declined. I left to grab some materials I needed for a project, maybe at most an hour or so, and came home to find he had passed away. I never did find out what was wrong with him. But I used the LifeGuard General Cure and it seemed to help.