Hey what size tank again? How tall is it? Was looking at your video again, the clowns seem fine for one. Swimming all over and even into the current. Surface movement seems to fine also.
If its tall you may want to think about adding a small nano power head left side towards the bottom facing the rocks.
Just thinking aloud.
"When creating an aqua scape, strive for the beauty of imperfection, as its art and there is no wrong or right, it's left open for interpretation" James Findley