Unwell Lepard Cory

[homerhotspur]

Bought 3 Corys, about 6 weeks ago. 1 didn't seem to grow and died a couple of weeks ago. Replaced it with another yesterday. Today found it on its back on the bottom. Later on the top and also just hanging vertically on a plant. Have moved it to a makeshift hospital tank. No obvious signs. Front fins are splayed apart.

I don't hold out much hope for it. All the water readings seem ok. The other Corys seems to spend most of their time just sitting on the bottom in a cormer near the air stone outlet. Thought this was just what they did but now wondering if they are also suffering. Any advice/comments please?

 

[WILDER]

Corys are more prone to bacterial infections.
Any red streaking in the fins or red patches on the belly or underneath.
Any colour change like being darker or paler in colour.
I would put all the corys in a hospital tank and use a bacterial med.
Once they lay on there backs sadly they don't tend to make it.