Bulk pack. Approximately 40 gallons Provides maximum surface area with the greatest possible mix of air and water. Cultivates nitrifying bacteria. Promotes gas exchange, increases dissolved oxygen level and removes harmful gases. Will not clog with organic matter. Manufactured of the highest grade thermoplastic material. Totally inert and non-leaching. Use in any type of Aquarium or Pond Filter to increase performance. Recommended usage: One gallon (3.8 liters) BIO-MATE for every 25 to 35 gallons of water (95 to 133 liters). Features Higher Surface Area Increase Biological Activity Provides Increased Aeration Creates better Water Quality Can be used individually or mixed in Filter Chamber