Something is killing my Corydoras!!!!

DeAnne

I have a 30 gallon tank that is stocked with 3 swordtails,4 platies, 3 leopard danios,3 kuhli loaches & 3 albino corydoras. All have been living peacefully for over a year... Until I purchased 4 additional corydoras. (I have additional tanks with salt and pepper corydoras that have produced eggs & babies)

Anyway, I purchased 2 large and 2 small albinos to put in the tank & every morning I wake up to find one injured. They would die within one day. It looks like they have a red band as if something squeezed it. I have never seen anything like it before.

I was wondering if this is some disease or illness that I am not aware of, or is one of the corydoras killing them?

Any ideas? Thank you in advance!

Byron

Corys do not attack each other, at least Ihave never seen or read of this, and I have maintained dozens of cory species for many years.

It is more likely some disease that arrived with the newcomers. Can you post a photo of one of the corys with the red band?

Byron.

TwinDad

What kinds of decorations do you have? It sounds as if they are hiding or trying to hide under something and injuring themselves.

DeAnne

I'll have my husband try to take a photo of it today - and will post it. I am a horrible photographer! LOL Thanks!

DeAnne

The only decorations I have in that tank are a couple of rocks with a piece of wood over the top - plenty of room for everyone to go under, and some live plants. But that was a great thought, thank you. (I actually had to get up and go check what decorations I had in that tank LOL)

DeAnne

I think I attached a picture of the corydora - I would appreciate any advice. Thanks

Attached Images

Corydora.jpg (65.0 KB, 37 views)

Byron

This is not meant to be disrespectful at all, but are you sure he was not injured to some degree when you got him? The dorsal fin is missing except for one ray, he is fungused, and those blood streaks. I do not myself think this is due to another fish in your tank from the list you gave us. More likely a disease that came with the fish.

I am not at all expert in disease and related issues, so hopefully someone with that experience will offer advice.

Byron.

bettababy

That looks like a very serious infection going on. I will do all I can to help you, but I need more information first.
Do you have a quarantine tank?
Can you please post your water parameters for ammonia, nitrite, nitrate, and pH?
Water temp?
Are any other fish affected?
How many corys are showing these symptoms?
How long has this been going on?
How long from appearance of infection before death?
What foods are you offering?

Don't do anything drastic like massive water changes, etc. If you are due for a water change please get the test results before you change the water. I will check back in later today to watch for your reply.

DeAnne

Unfortunately my Corydora did not make it. I originally had 3 and purchased 4 additional ones a few days ago. (2 small & 2 large) so I had 7. I lost one a day, 3 days in a row, I now have 4.
Every morning I would check the tank and one fish looked like it was beat up - it would die by the next day. The remaining 4 all look in great shape.

I did not put them in a quarantine tank (obviously I should have) I can't even tell now which are the originals except for 1 - I still have one small one left that I purchased a few days ago.

The temperature is 76 degrees & everyone seems fine but I am clueless as to what happened.

bettababy

I would suggest watching all corys in that tank very carefully. If you have a quarantine available this would be a good time to get it ready. There is a good chance this started out as a virus, for which there is no treatment... however, the obvious bacterial and fungal infection can be treated. (about a 75% success rate) This is common in corys in some areas, and the very reason why all fish should be quarantined for at least 2 wks before going into a main tank with other animals.
Take note of the store these fish came from and do not buy anymore corys from there in the future. If all of the tanks in the store run together with filtration, use the same nets, cups, etc in all tanks, or even have employees going from one tank to another without sterilizing hands and such first... then you don't want fish from any of those tanks.

If you wish to treat the remaining corys in a quarantine tank as a preventive, please let me know and I can talk you through it. It is best to catch these things before they get as severe as in the photo, because by that state it is usually too late, the fish are too far gone to survive even with medication.

Please keep us posted.