Corys Are Lopsided

[Rhykiru]

I just finished changing the substrate in my 20 gallon tank from sand to black gravel and this morning, i saw that my corydoras were on their side. They were still breathing and i kind of scared them so they went upright and swam away. When they stopped though, the just slowly flopped over.

Does anyone have any idea why this is happening?
this is only happening to 2 of my 3 corys (swartzch)

At first, i thought it was just that they werent oriented to the light because the substrate was now no longer reflective so they were confused.

Any help?

thanks

 

[Rhykiru]

OOPS i just saw that i posted it in tropical chat.

Would a mod be nice enough to move it to the emergency section please?

thanks

 

[rossyboy]

Not sure about that.... i own them and havn't seen that before EXCEPT when one had an illness.

Also... just a query, why are you changing from sand to gravel? Do you know that corys generally prefer sand?

 

[jollysue]

Indeed they do prefer sand.

It is probably stress, if there were no symptoms before. Corys don't have many defenses, but one is to play dead. Problem is the play dead sometimes is actually a stress thing and they don't recover. Keep the water Super good quality just in case their stress level compromises their immune system. I would turn the lights out and make sure they have lots of cover and quiet. Still keep an eye on them and try not to mess with them.

My long fin peppers lay on their sides, but it is relaxed. I have never seen any others "lounge" so to speak, and I assume yours are stiff with their fins out stiff. I don't know any other thing to do other than reduce the stress on them by leaving them alone.

Have you had them long?