Focus Phosphate Remover is a naturally formulated pool water additive that removes phosphates from pool water. The existence of phosphates in the water can encourage algae growth, as phosphates are nutrients for algae. Phosphate Remover is not an algaecide or algaestat and does not kill algae. Normal sanitizer levels will kill algae and Phosphate Remover helps with the sanitizer efficiency. Regular use of Phosphate Remover will help prevent the existence of all types of algae.