I went on Amazon and bought 90,000 knockoff Orbeez from China for only $30. I also bought a kiddie pool—it had soft, rainbow-colored walls. I was ready to live my best life.

The company says that one packet of Orbeez contains 150 balls (equaling about 3/4 of a cup after they are placed in water), so that means to get to 25 million of them Rober needed to use the ...