I'm a bit worried because my Cory Panda's keep going up and down on my window, not to get air, just racing up, and letting themselves drop back down and they stop about 1cm from the gravel.
They don't do it for air (I have one bubbling wall which takes a bit less than half the tank, and two extra smaller bubblers in two corners of the tank). All the water parameters are very good.
Is this normal?
I want to get 4 more, what do you think?
Here's a picture of one of the cuties.
![Image](http://i156.photobucket.com/albums/t17/kKreuz/My%20fish/erww3.jpg)
(Direct link, I can't resize it properly and it cuts the picture in half; http://i156.photobucket.com/albums/t17/ ... /erww3.jpg )