CO2 Beetle Counter is a CO2 bubble counter for large aquarium tank requiring a large supplementation. As CO2 bubbles rise in a spiral, you can easily count the number of CO2 bubbles. The design combines a playful sprit with practicality. *White diffusion filter part is made with glass, and vulnerable. We cannot exchange this filter part. In case algae appeared on its surface, please wash away with Superge, glass detergent. *Pollen Glass Series for AIR is to be connected with an air pump, and used for aeration during the night. *Use silicon tube for connection of Glass products