There are lots of variations to the procedures but this has been my favorite. To start with we'll need a few items:
To begin with I filled the tank 1/2 way up with water. The heater was then placed securely to the back and plugged in. The instructions on the eggs advise 85-90 degrees F.
Two lengths of airline were then attached to a four gang valve with two valves closed and two open completely. The gang valve was then hooked to an air pump with another piece of tubing. Two brass nuts were slide onto each piece of airline tubing and then an airstone was attached to each. The brass nuts serve as weights to hold the stones down at the bottom.
Both jars were filled almost to the top with water and 1 tablespoon of aquarium salt was added to each jar. The jars were then placed into the tank. The water level of the tank rises up to within a few inches of the top of the jars but make sure it's not over the top. The tank is used basically to heat the water in the individual jars. The airstones are then placed into each jar and allowed to settle down to the bottom.
Once everything is in place we observe the bubbles. If too much air pressure is going to the stones a third valve on the gang valve can be slowly opened to release excess pressure or a third stone can be added to the tank itself to circulate the heated water around more and reduce the amount of air going to the stones.
Using this method several more jars can be added to the tank as needed so that by the time one jar is used up a second can be ready to go.
When everything's ready 1 teaspoon of BS eggs will be added to one of the jars. The second jar is setup just so that it'll be ready for eggs when needed or in some cases if the water in the original jar starts to foul badly, I can siphon the brine shrimp out and move them to the other jar. Hatching begins in roughly 24-36 hours.
There are several methods commonly used to separate the brine shrimp from the water and eggs in the jar. The technique I used most commonly in the past was to remove the airstone from the jar. The jar is then removed from the tank and placed in a dimly lit location. A small children's night light is then hooked to an extension cord and placed up against the bottom of the jar.
After roughly ten minutes the eggs have floated to the top and bottom. The baby brine shrimp that have hatched have swam down near the bottom of the jar on the side closest to the light. A syringe or piece of airline tubing is then gently inserted into the center of the cloud of BBS and water along with the shrimp is extracted.
I usually run the water through a brine shrimp net and then release the baby brine shrimp into a second jar containing unsalted water that is approximately the same temperature. The tank can be used to keep this jar at the correct temperature also.
Afterwards the desired quantity of baby brine has been moved over the light is moved to the jar of unsalted water like before. After another 5 to 10 minutes the BBS have once again migrated to the bottom and the eggs that were collected have floated to the top. Repeat the extraction method from before, drain through a brine shrimp net and you are ready to serve.
The original jar is then returned to the heated tank. The unsalted jar is rinsed, refilled and returned to the tank as well. Replace the airstone. After about 3 days if you haven't exhausted all your baby brine shrimp they can all be collected and moved to a second salted jar for holding. Very few additional eggs will hatch after the third day and moving them to clean water can extend the life of the baby brine shrimp quite a bit.