facts about siamese fighting fish4. One speculation is that males that display more frequently during fights could have a much better possibility of profitable, and indeed this has been formerly established for B. splendens . Von Betegh first mentioned mycobacteriosis in marine fish in 1910. Mycobacterium marinum was isolated and defined in 1926 by Aronson as the reason for tuberculosis like lesions in the liver, spleen and kidney of tropical coral fish kept in the Philadelphia aquarium. This organism was at the start thought to infect only marine fish, but it has since been isolated from freshwater species and humans Barrow and Hewitt, 1971; Van Duijn, 1981.