This EPA registered product utilizes a unique control mechanism to kill and inhibit algae without harming the environment. Unaffected by heat, sunlight and evaporation, our product also outlasts and outperforms copper, enzyme and quat based products. A small dose of our product lasts up to a week or more and is very economical due to its concentrated formula. This is a non-hazardous, non-staining and non-foaming product when using the recommended dosage. It is safe for all wildlife when used as directed.