Thiobacillus Broth s used for cultivation of Thiobacillus species. The medium contains three inorganic sulphates and sodium thiosulphate. Phosphate serves as a buffer while sodium chloride maintains the osmotic balance of the medium. Growth of Thiobacillus thioparus and Thiobacillus thiooxidans is observed after 7 days of incubation at 25-30deg C.