Moses is Jewish and was born in Harbor City, California. He was a goalkeeper on the United States men's national water polo team at the 2008 Beijing Olympics. In the championship game, the USA team won the silver medal, defeated by Hungary. He was named to the Olympic all-star team.
In December 2010, Moses' silver medal was stolen by thieves when his parents' house was burglarized. The thieves also stole both a ring and a watch that he had been given by the US Olympic Committee.