Tadpoles, Water and Mud in a Rubbermaid

I dismantled a small half built pond in my yard a few weeks back, and as I
drained it, I found hundreds of tadpoles. So we dumped those into a
rubbermaid container, and dismantled the pond. Now I have rubbermaid with
100's of tadpoles, and some other insect life, in a rubbermaid that has
several inches of mud now settled on the bottom. I want to figure a way to
dump these guys into the main pond, but avoid the mud from going in.

Any ideas? I have overflowed the rubbermaid for days, and got some of the
tads out, but after awhile, they all swam to the bottom and avoided the
current.

BV.