Lubao Bags (also known as Kallax Balls) provides a nutrient-rich biofilm food source and safe grazing surface for shrimp. These long-lasting bags support the overall health of your shrimp tank. Perfect for shrimp enthusiasts seeking a balanced and thriving aquarium ecosystem. Suitable for Caridina and New-caridina shrimp. Constant food source for baby shrimp. Instructions: Soak the bag in some aquarium water in a cup overnight. Once soaked, place the bag directly on the substrate of your shrimp aquarium. Each bag will last for a minimum of a week. After a week, remove and discard the Lubao Bag. One bag can be used for up to 20 shrimp.