A PI(R) First Layer(R) Pure Laterite The API First Layer Pure Laterite is an ideal aquarium stabilizer you can use for your fresh water pond. It comes in an easy to administer granular form which makes it suitable for aquariums and is better compared to aquarium gravel. It creates a healthy environment for aquatic flora. It is most suitable for natural ponds. Features: Granular form Healthy environment Ideal for naturally planted ponds Item Specifications: Size: 20 oz: (560 g) box 50 oz: (1.54 kg) box Purpose and Benefits: In tropical streambeds, aquatic plants grow in a special clay called Laterite. First Layer provides an all-natural planting medium for aquatic plants. Ideal gravel additive for naturally planted aquariums.