Video 6 - shrimp actively swimming along tank walls can also be seen at bottom near white pipe
It took me a while to figure out this is not the bottom of the tank we are looking at, but the tank wall (shot from above).
If they enjoy climbing the walls so much, one might consider putting in vertical substrates instead of horizontal ones. Would also make it a lot easier to feed them. Well... I suppose that is what the white pipes are for.