I use -
28ppt (parts per thousand) of salt
28 degrees c heat
good airation/water movement(important)
They should hatch 24 hours later. Once they have hatched their nutritional value plumits within about 6 hours. to counter this, or to create a substantialy superior food for your fry, you can feed your artemia.
I syphon out the newly hatched bs (with an airline) into a pint glass. (bs are photosensitive and so are attracted to light. You can use a torch to 'lure' them to where it is easy to syphon them)
As a general rule, the eggs float, so it is a good idea to syphon the shrimp from the bottom of the hatchery, thus avoiding the potential for your fry to consume problem causing eggs/shells.
Once in the pint glass you can 'bioencapsulate' the artemia. This is the fancy word for feeding! Liquifry or any vitamin formula is fine, but be sure to only give the artemia 20-60 minutes to feed. (after this they will start to metabolise the formula).
Goodness, once i start talking i dont shut up do i? hope this helps, if you need more info let me know