Aquascape Sludge Cleaner Bubble Tabs disperse sludge-eating bacteria quickly, helping maintain a strong biological balance in your pond while quickly cleaning rocks, gravel, and filter pads. The tabs can simply be tossed directly into the pond, providing a fun and easy way to add water treatments to your pond. Our Sludge Cleaner Bubble Tabs have more than 500 million CFU bacteria count per tablet, allowing you to spend more time enjoying your water feature. Aquascape Sludge Cleaner Bubble Tabs are completely safe for fish, plants, pets, and wildlife. Each tab will treat 100 gallons of water and the full container treats 3,600 gallons of water total.