Pond Sludge Remover contains a proprietary blend of natural bacteria and other ingredients. It comes in easy-to-use water-soluble packets. This box contains 36 packs. Pond Sludge Remover eliminates sludge from your rocks, gravel, and filters keeping your pond or other water feature clean and clear. It is safe for fish, plants, and pets. The convenient packets make it easy to spot-treat any problem areas. Each packet of Pond Sludge Remover treats up to 1,000 gallons of water. Treat dirty ponds twice per week for two weeks. After two weeks, start using one packet to maintain clarity. This product is most effective when water temperature exceeds 45°F.