Water Temperature

Water temperature is pretty important. According to the hatching guide optimal hatching temperature is between 75°F and 80°F.

However according to this experiment, it was "concluded that brine shrimp thrive in colder conditions. Although more total eggs hatched in the heated environment, the majority of those eggs died soon after hatching. All of the brine shrimp that hatched in the cooled environment lived, as well as in the room temperature."

So keeping track of a tank's temperature is very important. I have seen a lot of people go out and buy high dollar aquarium thermometers to keep up with the temperature in a small Ocean-Zoo. This is not necessary.  Just get little stick on thermometers from Wal-Mart.