They look like they have been newly introduced to that tank, the dancing in the corner is typical behaviour when they are moved (or when a water change is carried out).
Mine (Oblonga and Kuhli) swim in my bubbles all the time. I have about 6 of each and at any given point during the day, there are 2-3 doing it. They swim all the way to the top of the 29 gallon and seem to be frolicking.