At the 2013 World Championships in Chungju, South Korea, he partnered with Kathryn Ross to win the gold medal in the Mixed Double Sculls TAMix2x. They were coached by Gordon Marcks. With Ross, Bellis won back to back gold medals by winning the Mixed Double Sculls TAMix2x at the 2014 World Rowing Championships in Amsterdam, Netherlands. This victory was ranked #39 in the International Paralympic Committee's list of moments of 2014. Bellis and Ross finished second in the B Final at the 2016 Rio Paralympics.