If you have a good hatch from around 1/2 dozen females you will run out of zooplankton in a hurry (several days) to feed them. Once the fry absorb all the stored food reserves you will see large die offs.
Are brine shrimp small enough zooplankton for small young fish other then just minnows?
Would it be worth hatching brine shrimp and letting them go into the pond?
Cheers Don.