if you get eggs without cycsts, you can just add them to the tank. Though as you will find out when trying to hatch brine shrimp, all the shells get left behind, rot and decompose, and also, they could kill corals and small fish. But if you put the cyst-free brine shrimp in the tank (i believe ORA makes some), they are unlikely to even reach a hatching level because they will be taken out by your protien skimmer, your corals will eat the eggs (which is why ORA makes them without cysts, to feed corals), they will be caught in your mechanical filtration, ect. But those HOB brine shrimp hatchers are a rip off if you ask me. They sell one, it is just a platform and some airline tubing. spend 5 bucks on an airpump and airstone, and get a two litter soda bottle and cut off the top. It even comes with eggs. And then you have a brine shrimp hatcher.