i'm not an expert, but i use tank water (unless you have the packets that have salt in them)
i use about 1/4 tsp brine and 1 liter of water
i put a light to them and airiate for 24-36 hrs, then i remove the light and prop a flashlight so it shines in the bottle about half way up, after about 15-20min most of the brine will be in the light beam (attracted to it)
i then suck them out with a turkey baster and squirt them into a brine-shrimp net, rinse gently and then feed
hth