Plan to setup a new planted Volcanic Shrimp tank

[GodOfDeath]

hello everyone ! I recently bought a cryshaven eco-system with 2 "wondershrimp" inside which actually turns out to be Volcanic Shrimp aka Opae Ula. keeping them in a small area seems to be too cruel for them, as such I have plan to setup a proper tank with suitable plants and everything and also add in a few more volcanic shrimp inside but I am a total noob at keeping shrimp. would appreciate if any bros here is able to guide me here.

I understand that they need brackish water, what kind of salt do I need to put in ? the ratio should be 1:3 right ? with 1 being salt water and 3 being normal water.