that's awesome! How active are they? The ones I saw at the pet store were a little less active than some of the other corys. It's not like they just sat there, like some of the other species, but they didn't move around as much as others...
Hi. Trying to determine anything about a group of Corys, by using the way they act in a tank at your lfs, is not a very good indicator of anything. The same group of Corys, even in your perfectly set-up aquarium at home, will display certain behaviors at different times. A group can hide under cover for days on end and all of a sudden they are out in the open for days at a time. They may shoal as a group and then one day, one or two decide to cruise the tank on their own. Oftentimes a fish from one group will join another group for a short period or days. Oftentimes a fish, in perfect health, may rest or cruise on its own, regardless of the actions of the rest of the group. Additionally, trying to ascribe any type of significance to these behaviors is a futile exercise, and to my way of thinking, a perfect example of anthropomorphism.
Fish are not happy or sad, friendly or nasty. They are either well maintained in which they will display optimum health - or - they are poorly maintained and exhibit behaviors that we might interpret as "sad." They don't "long" for companionship and a lone Cory in a tank can survive for years in perfect health and "happiness." lol. Does that mean to say that fish do not display certain behaviors that we can interpret as the aforementioned "feelings?" Of course not, but putting our feelings onto our fish, or trying to place our interpretation of what those behaviors represent at certain times is well, you know - - - - - - - - more of those mental gymnastics, to use a politically correct term.
Additionally, you can't even judge what a group of fish will do in your tank, as opposed to another person's tank. There are so many variables that are involved in maintaining fish, that it is almost impossible to predict how a certain group of fish will acclimate and "enjoy" their new home. Trying to gain information from fellow hobbyist can certainly be very helpful in making purchasing decisions, but I think, in the end, if you want a group of fish you should get them, provide the best you can for them and then see if the fish exhibit the type of behavior that you deem necessary f you to want to continue to keep that fish.
I feel it is best to just let the fish live their lives without excessive demands from their keepers that they should shoal more or spend more time in the open. They are not circus animals that can be trained for your amusement. Enjoy fish for what they are, rather than being disappointed in what they are not. If you like fish that shoal as a group in midwater, then there are realistic purchasing opportunities for fish that will precisely meet your requirement. However, if you purchase a specie that tend to be more "shy and reclusive" and keep poking them with a piece of rigid air line tubing to get them moving - well, there's a special place in hell for fish keepers who treat their fish that way. Fish are not pets. Sure, you can get an Oscar to take food from your fingers. Did you train it? I think not. I haven't seen an Oscar, yet, that won't take food from your fingers. As much as we proclaim to love our fish, well, they ain't loving us back. As much as I love my fish, more than anything on the planet (except for my dog), I always have to remind myself that a cockroach is infinitely smarter.
Now - with all of that beings said, here's something to ponder. If you see a group of C. adolfoi at your lfs and you really like the fish, but you ain't crazy that they look kinda lifeless, why not take them home and see if you are able to provide them more of an environment that would be to their liking, which in turn would make you and the fish, "happy, happy, happy?"
I love my C. adolfoi (just pulled 15 eggs, yesterday), but their behavior runs the gamut. I never give it a second thought and I leave them to just go about their daily routine with as little interference from me as possible. This is also why I make absolutely no concerted effort to spawn Corys. They've been spawning for hundreds of millions of years with no help from man (sorry, creationists) and I firmly maintain that they'll be spawning away when humankind has been wiped from the face of the Earth.
Try them. You'll like them - and if not - just move them on to another enthusiast. Yes, perhaps they will be "happier" living at someone else's house.
- Frank