Our algae removal tablets (boxed) contain copper oxide, activated carbon. It can help slow the spread of algae in a fish tank or pool and make the water clear. It can solve the problem of algae deposition and help you change the water in your aquarium faster. Improve the purity of the water, reduce the odor produced by algae in the water, and prevent algae from destroying fish ponds and fish tanks. The ingredients are safe and mild and will not affect the fish. Its use method is very simple: take the right amount of this product into the water, let it dissolve after a period of time until the algae growth. Remove algae quickly, purify water and keep water clear.