What is going on with my sterbai??? So confused

So I fixed my parameters and get them back to normal, but one of my corydoras are dead now...
There's only a few corydoras with excess slime and fin damage, while the others are BEAUTIFUL, with no issues at all.


This is the one that died:

And here are what the majority of my corydoras look like:


I'm so confused at what is going on... It's not like it's something that's spreading, and they don't ACT irritated, cause they aren't flashing or scratching themselves in things, they just have bad fins and slime...

Sorry but the image of the dead fish are just too blurry to even give a hint as to a possible issue.

Still, you said that you got water parameters back to good and that makes me wonder what was initially off. Sometimes you have to correct water parameters gradually as some fish are more susceptible to quick parameter changes than they are to the initial bad conditions.

jaylach said:

Sorry but the image of the dead fish are just too blurry to even give a hint as to a possible issue.

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It's spoilers. Click it and it unblurs. Sorry for not specifying lol

jaylach said:

Still, you said that you got water parameters back to good and that makes me wonder what was initially off. Sometimes you have to correct water parameters gradually as some fish are more susceptible to quick parameter changes than they are to the initial bad conditions.

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Yah, true... I thought by doing it in the way I did was fine but maybe not

I would go online and look up images of Oodinium infestations, and if it doesn't ring a bell, check related parasites. If you let the tank slip, it's a possibility worth eliminating.

GaryE said:

I would go online and look up images of Oodinium infestations, and if it doesn't ring a bell, check related parasites. If you let the tank slip, it's a possibility worth eliminating.

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They only have a few of those symptoms though. I'll look into it further, but I really don't think it's that from everything I've seen

The main symptom would be a greyish or rusty film on the skin of the fish, often concentrated on the head behind the eyes and along the spine. If it has cut loose, there will be fish deaths.