Like with any macrobrachium if you keep them well fed they are far less likely to eat the young. The biggest risk is probably from filtration as they have a shortened larval phase (freshwater), and too powerful filtration will suck zoes in far more easily than it does shrimplets.
Really nice, and less common in the UK, variety of shrimp though, and far less predatory and aggressive than the other macrobrachium species.
Ade