Know what the labels mean
Neocaridina and Caridina are different genera of freshwater shrimp, and each includes species with distinct natural histories and husbandry needs. Hobby shorthand often describes Neocaridina as more adaptable, but that is not a guarantee for every line.
Some Caridina varieties are kept in softer, more acidic water than many Neocaridina colonies, yet the genus is too broad for one universal comparison. Confirm the exact animal and seller's care information.
Start with the water you can maintain
Test your aquarium and ask the breeder how the shrimp were raised. A suitable, stable match is a better basis than buying a species and rebuilding the tank around a generic chart.
Do not keep both together solely because they are shrimp. Their preferred conditions may differ, and species-specific breeding and tank-mate goals matter.
For your own tank
Before choosing between genera, identify the exact species or color line rather than relying on a broad store label. Ask for the water in which the animals were raised. Matching your stable setup to that information is more reliable than following a simplistic hard-water versus soft-water rule.
Use these as general hobby references. Test your aquarium and confirm product guidance before making changes.