I really like the minimalistic style! The flows have a very nice animation and they are animated (lively), as they have different behaviours (speed).
The left/right controls are good. Sometimes I wished a tighter curve. A bit tiresome was the hitting the space button to keep them close.
I was not able to finish a level. I think I had all flows, but nothing opened. Before that one of the flows was hiding between border and line, and did not get much out of it.
The music was fitting, unfortunately it did not loop and ended after a short time.
Generally, I think there is a lot of potential to make this bigger (exploration, underwater, mediative, ...)