Black Neons Swimming Vertically

[Lynz781]

I've not long had these guys but I've noticed that ocasionaly they like to "hover" almost vertically in the flow of the filter. When they are not doing that they appear to swim ok. They are eating well too. As I've said I've not long had these fish and probably still getting to know them. Is that just what they do?

Here he is on the right:

 

[The-Wolf]

that is what I call swimming-on-the-spot (think running on the spot)
perfectly natural for black neons and many other small river fish.