Ideal as a bacterial starter for filters or to enhance the bacterial activity in your filter, just add the amount of tablets required based on your pond size! Sludge Klear also helps prevent and breakdown blanketweed by removing the key nutrients that blanket weed need to survive and thrive .....nitrates and phosphorous. Targeting these nutrients means that blanketweed struggles to survive and grow while the bacteria breaks down their anchor points. 1 tablet treats 5,000 litres (1,250 gallons) of water, but we recommend a double or triple initial dose to really get the bacterial colonies active and starting to dominate the system with GOOD bacteria! Sludge Klear works as low as 4°C which allows for treatment in winter to reduce the effect of green water in spring. With 100 billion bacteria per tablet, Sludge Klear can be used to solve sludge problems or as a regular treatment for protection. Treat all year to return your pond to perfect health. Give that sludge a nudge!