Why would you want to grow out brine shrimp, just curious. If you want full grown brine shrimp, it's way more cost-effective just to buy them. You can buy a vial for $3 that lasts 10-15 batches, and you can always down the batches so you're not wasting as much. A batch of eggs will create several hundred thousand bbs, some will die. On top of that, BBS lose their nutritious value for small fish as they grow and use their nutrients for growth instead of giving it to fish.
If you are gung-ho about it, any spirulina powder will work. You can buy it from a health food store (little expensive, but it lasts forever). You could also just crush up algae wafers, as stated above.
