The ASTM D5589-19 standard test method is used to determine the tolerance of paint films and related coatings to algae fouling. Algae growth is a FAQ that affects film performance. This standard uses an accelerated test method to evaluate the resistance of different Coatings formulations to algae under specific conditions. Although this method can provide a comparison of the ability of Coatings to fight algae, it should not replace exposure testing in the actual environment. Users need to have a basic microbiological technology to ensure the accuracy and validity of the test.