Bromothymol blue paper is widely used as a pH indicator in various applications. It changes color based on pH levels: yellow in acidic conditions (pH below 6.0), green in neutral conditions (pH around 7.0), and blue in basic conditions (pH above 7.6). It is particularly useful in educational settings for teaching students about pH levels and acid-base reactions. In laboratories, it helps quickly determine whether a solution is acidic, neutral, or basic. It is also employed in environmental testing to assess the pH of water samples, ensuring they meet safety standards. Additionally, it is used in aquaculture to monitor water conditions for optimal fish health. Its simplicity and reliability make it a valuable tool in both scientific and practical contexts.