Hello.
No in the video the fry have nothing to fear from tadpoles they are big enough.
But the Yellow-perch larvae (see the little video) unlike the tadpoles at this stage the tadpoles seem to grow quickly, and with the light I put them in the presence of each other.
The occasion make the larron.(Opportunity make the thief).
https://www.youtube.com/watch?v=BfJoS-37IsE&feature=youtu.bePerhaps I'am completely in the field.
This spring I will put tadpoles and larvae in a bucket and I will see.
A+