Yes, Stupid Question, But Poisonous Corydoras?

[brynneth]

hey, i have an odd one here. i have a nice little eclipse tank in which i am housing my friend's cory cats while she is at college. i cant actually I.D either of them because they are both uncommon species and i've forgotten, but i can ask her and get back to this if its relevant. i do know that one of them is an unusually large pygmy cory that looks nothing like my own little school of pygmies and that the other one is something large, black and interesting from venezuela( i think). they school together and are quite happy on their own but they seem to be killing off my invertebrates which is making me sad. i added a pair of yellow clams a while ago who had been doing just fine, but as soon as i put them in and they started sticking their tongues out to dig, they touched the black cory. they pulled back in and then a few days later they fell open dead. i figured i had done something wrong water-wise or something but the other day i added a nice little nerite snail that was healthy in the tank at the store, active in the bag, and then once again, quite dead after contact with the curious corys. they arent eating it... but still, i am perplexed. i was gonna try a shrimp but i'll skip it if there's some basis to be concerned. tested the water and its fine, nothing is out of decent levels. help? i want snails...

 

[jollysue]

It is known that some or all Corydoras can release a poison when they are bagged that will poison them. It is assumed--I assume --that it is a defense measure that they use and backfires when they are in an enclosed space.

There is much about the Corydora that is unknown and unresearched but seen in observation.

On the other hand, I have snails in all my tanks--except the tanks with loaches, and they are fine in spite of Cory tank mates.

I have shrimp in several tanks with Corys and ADF with Corys. I have not seen any issues.

The Cory or some Corys can also "sting" with their sharp spines.

So I can offer nothing conclusive or even suggesting your experience. Corys will eat snails if they are out of the shell....