Help!! Lethargic cory :(

[Shadowraven]

This fish is still sick. That is not typical behavior for a Corydoras. Can you describe his behavior in more detail. Also describe the conditons he is in/around. Things such as: Any chemicals or odors in the air around the tank, tap water quality unchanged, no chemical or metals in contact with the tank, anything new added to the tank recently, has salt been added to the water. Anything you can tell me will help.

[Big-j]

None of those have happened and all my other fish act totally natural, I added 12 RCS the day before the first died, now two are dead and this one is still sick

[j2112j]

Not sure of your oxygen levels but you may want to try lowering the water level a bit, so the filters are splashing more, if they aren't already.
This idea helped someone elses cories so maybe give it a try and see if they perk up after a day or two ?

[Big-j]

Ight I'll give it a try the other two cories are fine though???

[j2112j]

Ah well, from your 1st post it read that one had died, then later another one started showing problems. I was thinking the two that are fine may also start having issues. It seems to be only the cories right ?
I've read that cories can have issues with lack of oxygen (perhaps all bottom dwellers), so increasing oxygen is an easy way to check.

[Shadowraven]

I wouldn't think that corys should suffer from low oxygen before other fish do. They can supplement their oxygen by taking in bubbles of air from the surface. This air is then absorbed through their intestinal lining into their bloodstream.

If you don't have anything contaminating or affecting the water then the only other thing I can think it would be is an internal infection or parasite. These problems are best dealt with a medicated antibiotic foods. There are several on the market, most of them should be OK to use. A gram-negative antibiotic is the most common to use.

[Big-j]

Ight I'll look into that

[Big-j]

Well he died this morning I woke up and he was upside down tangled up in the plants not breathing... RIP Maximus, Deucimus, and Ron

[Tasha]

Sorry to hear that, and so strage its only your corys...

[Big-j]

I know it was weird, hopefully the other two will be fine, I'm gonna go get three more to complete the school in a few hours

[angloe1]

Awww sorry!

[Shadowraven]

I'm sorry that we couldn't save your cory. Make sure that you keep a close eye on the others for now. At the first sign of trouble or strange behavior, let us know. You may have gotten a sick or injuried batch from the LFS. Let's hope it gets better from here on out.