the first betta I had with them (the one in my avatar) got along with them great. the first day I had them the corys were freaking out cus they were in a new tank and one landed on the betta's head but the betta didn't really care. The second betta with them was curious about them but could care less, unfortunately, thatt betta died soon after from ich (which the cories surprisingly never got). This one I have with them likes their shrimp pellets and pecked at one when it got in the way once, but other than that I have never seen the betta react much to them. He lived in a tank next to them (divided tank) since I have had him prior to just now living with them, so he might have been used to them. But maybe my cory cats are just boring or something. who knows.