At Fullerton, he was coached by International Hall of Fame inductee Jimmy Smith, who was an Officer in the Naval Reserves, coached at the Naval Air Station at Los Alamitos where Horn played Water Polo, and coached the U.S. Water Polo teams at the Pan American Games in 1955 where Horn would play and medal.

[9][10] After attending Fullerton College, Horn served in the Naval Air Force during the Korean War in the early 1950s.

In 1957-58, while Horn was playing Water Polo at CSU Long Beach, the team won the PAC Conference Championship.

[1] He was a member and Captain of the American water polo team that placed fifth in the 1956 Olympic tournament, where he played five matches as goalkeeper.

Four years later he finished seventh with the American team in the 1960 Olympic tournament, competing in four matches as goalkeeper.

[2][1][4] He led the swimming and Water Polo program at Cal State Long Beach from 1959-1965, where the team won the 1959 PAC Conference Championship.

[13] During his coaching career, he mentored 36 first team All Americans, and 26 Olympians in swimming and water polo.

[1] Horn enjoyed lifeguarding, riding horseback, surfing, waterskiing, travelling, and spending time with family.

[1] Horn served as President of the Southern California Water Polo & Swimming Association.