Know what RO water lacks
Reverse-osmosis filtration removes many dissolved substances, including minerals shrimp use. Its low starting mineral content can be useful when a keeper needs a consistent base water.
Neocaridina still need suitable mineral conditions. A shrimp-specific remineralizer is often used to establish GH and, depending on the product, KH.
Mix by test, not by guess
Follow the remineralizer label and test the prepared water before using it. Calibrate the process in a separate container so each batch is consistent.
Avoid adjusting a tank by pouring dry salts directly over shrimp. Keep records and introduce a new water source gradually.
For your own tank
Store RO water in a clean, labeled container and test the remineralized batch before it reaches the shrimp. Pure RO water and prepared aquarium water are not interchangeable. A consistent recipe makes future changes easier to compare.
Use these as general hobby references. Test your aquarium and confirm product guidance before making changes.