The Dymax GA102s Glass CO2 Diffuser is made from ultra-clear material and high-quality ceramic discs to provide optimal carbon dioxide diffusion. It is durable and compact, making it easy to install. It should be placed at the bottom of the aquarium for the best results. When the ceramic disc becomes clogged, it can simply be soaked in bleach water for 3 to 5 minutes, then rinsed with running water and reused.