Gerald Brommer studied at the Chouinard Art Insititute and Otis Art Institute in Los Angels. He studied privately with Robert E. Wood. In the 1950's, he focused his energies on watercolor.

A feature found in many of his paintings was Brommer's interest in the local geology and rock formations which he included as parts of his compositions.

He is best known for California landscapes and seascapes, but has painted in the Southwest deserts and in Europe, where he enjoyged painting European city scenes. He was a recognized teacher and authoer, writing 18 art instruction books and articles in numerous art magazines. He served as president of the California Water Color Society and the West Coast Watercolor Society. He has held 110 one-man exhibitions.