Corydoras Aeneus don't school together

LebronTheBetta

I bought 4 albino Cory Catfish for my sorority in my 20 gallon. All have no visible issues and eat. I vary their diet with algae wafers and shrimp pellets. I just bought them like, a few days ago.. Sometimes 2 or just 1 of the Cories won't swim with the others and lay still. There are always 2 together, but the other 2 are just by themselves. The "outcasts" move time to time but just lay still otherwise. The tank is cycled and heated to 77F-78F. The only other living creature is a female betta, 5 more to come soon. I'm also buying 2 mystery snails later today.

Any ideas? Maybe the temperature is too high for the catfish?

Jakiebabie

I have had up to 8 Cory in my 75 gallon and they have never schooled together. They I believe are more comfortable knowing there are others in the tank with them. It is interesting when I do add new comers to the tank, the others will come and greet them and they all go off together. Later I find them all over the tank often alone.
Some in here have been lucky enough to have baby Cories.... I want, but never have had any to my knowledge.

LebronTheBetta

I guess that makes sense. They're shoaling fish, right?
I guess baby Cories are pretty cute to think about. ^.^ But I have a lot more to learn about them before breeding. Thanks Jakie! :)

Jakiebabie

They are described as shoaling and needing groups but they certainly don't "school" like regular swimming fish will. Ya, agreed... baby Cories would be amazing to see.

Ogre44

Yeah, mine hang around each other more than with each other.
I think they just find comfort in knowing they have fellows close by.

Byron

Jackie's point is well taken; we sometimes get tripped up over meanings. Shoaling fish, which applies to all corys, means that the fish must be in a group because in their habitat they live in groups and are programmed by natural selection to require this. The more the better. But they do not necessarily swim around the tank as a group; some species do this more often than others. Most will do this when stressed. Spawning activity brings them together in groups. But the important point as others mentioned is having several of the species in the tank, or several of mixed species. They know they are there, and that settles them.

To your specific issue, this is perhaps due to the move. Corydoras do not like being netted and moved, this is highly stressful and I have noticed that some fish will take weeks to recover from a simple move from one tank to another. They are skittish by nature, as anyone who has ever seen them in their habitat can attest. So give them time; keep them comfy with no unnecessary interference, and they should be fine.

Byron.

cpwebsite

As long as your corries are healthy that is good. Fish tend to school when their is a natural threat or when they are going into an unknown region together which may contain threats (larger fish that won't eat them, or if they are kept in a larger aquarium). Getting more of them may also help them out with school.

Corries aren't know to be extremely tight schooling fish however. Good luck!

Thoth

I just moved some of my Violet Cory in to a breeding tank and they are schooling very close together; its been 3 days now and they are still scared to death. Its not a heavily planted tank, which seem to also increase schooling. I am sure that once they get used to the tank they will spread out a bit.