The Two Little Fishies NPX Bioplastics are specially designed biodegradable plastic media made from bioplastic polymers, providing a slow-release organic food source that promotes the growth of bacteria capable of absorbing nitrate and phosphate. These beneficial bacteria can be harvested by protein skimmers, naturally reducing nutrient levels in your aquarium water. Additionally, they serve as a nutritious food source for filter-feeding invertebrates like corals, clams, sponges, and feather dusters, enhancing the health and vitality of your reef ecosystem. NPX Bioplastics are most effective when used in a fluidized reactor such as the PhosBan Reactor 150 or 550, where they should be placed in NPX screens to maximize their performance.