brackish water shrimp

I have preggers Amano and Ghost shrimp and they always have eggs. None of the babies stay alive because I dont have them in brackish water. I am wonder what type of salt to use to make the water brackish? Aquarium salt, marine salt, table salt?

I have one 3+ year old shrimp and 8 others that are homing in on being with me for 2 years now. When researhing them, I kept reading that they are nocturnal. Somewhere, I did read once that they were active during the day, so I decided to go ahead and give it a try. Mine are active 24/7. Bc...