Effectivenes of

Industrial development poses a serious threat to marine ecosystems and biota in Indonesia. Waste released into the environment includes inorganic substances such as heavy metals Lead (Pb) and Cobalt (Co). An effort to restore contaminated environments is bioremediation using Halimeda sp. It is an alga capable of acting as a bioremediation agent through phytoremediation. This study aimed to determine the effectiveness of Halimeda sp. as a bioremediation agent for seawater contaminated with the heavy metals Lead (Pb) and Cobalt (Co). The study was conducted at a laboratory scale by culturing Halimeda sp. algae in 500 ml glass jars with heavy metal concentrations of 1.5, 3, and 6 ppm. The results of heavy metal content testing showed that Halimeda sp. are capable of absorbing heavy metals. Lead (Pb) absorption at concentrations of 1.5, 3, and 6 ppm was 87.83%, 90.17%, and 98.50%, respectively, and Cobalt (Co) absorption at the same concentrations was 99.17%, 98.40%, and 98.01%, respectively. These test results indicate that Halimeda sp. has a high potential for remediating heavy metal Lead (Pb) by bioaccumulation via absorption.