waterdrop
Enthusiastic "Re-Beginner"
No, you've got it right, that sounds right about the differences between the three and yes, it's all about groups. The corys go wild with really big groups, they completely change character, becoming playful and all looking for currents to shoot around in together. There have been videos of hundreds of them doing this in the wild. Below a certain number they just sit on the bottom (although this may be a normal part of "their day" even when in healthy groupings.. I wouldn't be surprised.)
~~waterdrop~~
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