I didn't realize how many Sea Monkey eggs there would be in a 1/2 teaspoon of eggs, but I can assure it's a lot. I have the little things coming out my ears! My estimate on the number that hatched is somewhere in the ballpark of 200,000 based on the number of eggs per gram! I have them in a 1 1/2 gallon tank with an aerator and a small heater. When you look into the tank the whole thing moves! I can't imagine using the whole teaspoon of eggs that I was supposed to use!