[mistergreen]

The cherry shrimp most likely won't be able to catch the daphnia but will feed on any dead daphnia.

Don't worry about the daphnia multiplying. If you don't feed them they'll die off.

 

[mistergreen]

I believe you're right. Daphnia are too fast for shrimp to catch. Even bottom feeders like ancistrus are too slow and don't hunt down daphnia. However, daphnia will feed on shrimp food and will likely multiply if there are no fish to prey on them.

Daphnia are filter feeders. They feed off particles, algae in the water column. I wouldn't say they can't eat shrimp food but not likely.