Enough hiding places and plants should be sufficient, as long as nothing is eating the adult shrimp the babies should be fine. The female carries the eggs on her body. She carries them on the outside of the underside of her tail, held in place by the small swimmer legs. We literally do NOTHING to help our cherry shrimp in a 55g with BN pleco, corys, baby angels, a male
betta, aside from providing hiding places. The hiding places we've provided are a large piece of
driftwood with java moss and various small plants attached, and a piece of
PVC pipe that the plecos and cories play in.