AlgExit – it tackles Algae. Algae are produced when an aquarium is not well balanced. Causes of an unbalanced aquarium are the excessive feeding of fish, too many fish in an aquarium, excessive lighting or excessive fertilization. AlgExit is a safe and effective product for combating almost all types of algae in a freshwater aquarium. Algae, such as beard algae, brush algae and filamentous algae, are effectively wiped out.