Pondmax Blanketweed Blitz is an infusion of all natural minerals and additives which when added to your pond will successfully combat blanketweed. Safe to use with water lilies and pond plants. Application rate is one heaped teaspoon per 300l of water. We recommend mixing with water and pouring around edges of pond where blanketweed is growing. Repeat application after 1 week. Each container treats 5625 litres as a single application.