The issues with fry in with the shrimp are over feeding, happens as frequent feeding (but not over feeding) fry gives them a good start, can lead to too much left over food and/or causing water quality issues. Need to make sure to do very frequent pwc, a little clean up crew maybe like Ramshorn snails.
So then excellent filter /water turnover is important. But not too fast of water returning to the tank causing a whirlpool or too high current. Also having a prefilter or sponge over the intake so babies don't get sucked up into the filter.
Shrimp won't eat the fry unless it is already sick, dying, or dead (scavengers), and fry won't eat shrimp unless they can fit in their mouths...hungry!