Cory Sterbai toxin

[bixx]

Hi, new to this forum and to corydoras. Three weeks back, we bought a group of 5 juvenile corydoras at a big fishkeeping event and they were labelled elegans. I've now learned they are actually sterbai. They've grown a little bit now but they are in a 180L tank I've recently rescaped and so the plants are still growing. Not exactly their ideal scape at the moment. I took over another 5 adult sterbai (I still ask myself why? WHY?!). I honestly did not expect them to be something of the jumbo jets of corys but couldn't back out of a gentleman's agreement. Now seeing them, I think that maybe 10 in a 180L is a bit much. Moreso, I've learned about their toxins quite belatedly -- strangely it's not information I came across while trying to figure out what species we actually bought. The 5 adults survived being transported in a S/M sized plastic box. The water was yellowish but that's the color of their former home water. I clean my hardscape (XL river stones) every other day or with an electric toothbrush, but now I'm worried they'll get stressed and basically go nuclear in the tank and bring down all my other fishes with them. The small ones seemed to be ok and have settled nicely, but the adults are used to a river biotope (450L) with lots of hiding places and dark water. How worried should I be about this? And I usually clean hardscape with no gloves on. Is their toxin harmful to bare skin/general health? (Of course I wouldn't want to get a sting from them but I doubt they will come near my hand anyway). As a newbie to corys, I'm really worried about tank cleaning (including doing major water changes) and spooking them out and having them release toxin into the aquarium with all its possible repercussions. Hope someone can enlighten me. Thank you in advance. (PS, they are so thorough with the sand substrate that they are also digging out the tropica nutrition tabs!)

[bekateen]

Hello bixx. Welcome to Planetcatfish.

As for your questions about Corydoras sterbai, aquarium size and toxins, I think your tank size is fine as long as the tank isn't also stocked with lots of fish. About the venom, corys release it when stressed. If you allow them to live their lives in the aquarium and don't stress them, the probability that they will release venom is almost zero. That said, I am a bit concerned that if you are cleaning your tank surfaces daily, you might be cleaning too much. That might stress them over time.

If your cleanings are minimally intrusive, they should be okay. But otherwise I'd do those scrubbings less frequently.

As for your own bare skin, if you were exposed to venom it is harmless unless you have open wounds on your skin. Even then, the bigger risk to you is bacterial infection, not the venom.

Good luck,
Eric

[bixx]

Thanks for the reply. It's the beginning of the dry skin season, so there is that occasional dry skin shallow cut. I don't think they puffed anything out after I transferred them, seeing as all my other fishes are ok. But I think I am mostly intimidated by their size and then the unknown factor of toxin. My adult sized diamond tetras (8) are not happy with the bare tank (waiting for the vals to grow) and so have taken to spending more time at the bottom where it is looking really crowded with the big corys (who don't seem intimidated by them). I fished out one of the juveniles who seemed to have perished from what looks like red blotch disease (never had this in any of my fishes) - surprised me, since they were all doing so well. Have to keep an eye out for that too now.

[Bas Pels]

While Corydoras sterbai is said to be amongst the Corys with the most potens venom, ist is harmless for people.

still, cleaning the rocks every other day is far too much cleaning. That would stress any fish.

The rocks might gget a greenish blush, which will help getting the water good. But even if that does not happen, they will ,when given enough rest, be overgrown with good bacteria withs help in the nictrogen cyclus - ammonia -> nitrite -> nitrate - which is ar, far less toxic than the other products

So you better leave them where they are.

[bixx]

Thank you! I will leave the rocks a alone in the meantime. I have a mature filter media from the old aquarium which I am using for the new one, I've only used strips so far to test the water (in all my history of having 3 aquariums -- from small to medium to large) and all seems to be within order though a water test kit is on my buy list as soon as my budget permits. I am seeing blue green algae on the smaller stones so I've been cleaning the stones a bit more than usual. Still figuring out the reason: lighting (unfortunately cannot be dimmed - standard juwel led lights -- still looking for the best solution, possibly floating plants), filtration strength, ammonia, maybe even de ferts. But honestly, since getting the adult corys and learning that these sterbais have a rep, I've been hesitant to put my hand in the tank for fear of stressing them out while they are still acclimatizing to their new home (they have been swimming around but mostly seem to want to catch the water wave from the skimmer outflow). Good to know the venom is harmless to humans (i do have 9 of them now) . lol. The priority would still be the safety of the fishes though so hopefully they all settle soon.