wtf is my cory doing?

That's the reason cory tanks must be pretty well covered, and the water level must be at least 1" below any reinforcement glass piece that crosses around the surface of the tank.

This will avoid the need to pick a cory from the ground- or he smashing his brain out
 
What's really funny is when the cory dashes to the top, realizes something's in its way -- a floating bit of plant, or another fish -- then swims back down a quarter of the way, then spazzes out and darts to the top someplace else to get to the surface. Occasionally this process repeats itself a few times in a row as the cory can't seem to stop bumping into things...
 
Plecos do the same thing, and I believe alot of other catfish share this trait. They do "swallow" air. It has something to do with maintaining equilibrium & buoyancy in conjunction with the fish's swim bladder I believe.

I had a pleco that used to do this so loudly it would wake me out of a dead sleep from the next room.
 
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