Can easily drive even Nano Air pumps, suitable for fish tanks. MODEL: ASR-020. Spray volume: 1L/min. Recommended air pump power: 2W-4W. Made of high-quality non-toxic mineral material. Suitable for 4mm inner diameter tubing. Compact diameter: 20mm. Net weight: 120g. Soak the stone completely in water for approximately 1 hour before use. Comes with 10 ball air stones. Spherical Air Stone An airstone is designed to gradually diffuse air into the tank and supply oxygen to fish, making it essential for aquarium enthusiasts. UnicLife air stones are made from high-quality, non-toxic mineral materials. Through high-temperature sintering, the stones are sturdy and durable, provide high dissolved oxygen levels, and produce even, fine bubbles instead of large ones. Made from high-quality, harmless mineral material Produces small, consistent bubbles Helps maintain oxygen levels for healthy fish What kind of airstone should I use? Understanding the basics: A larger airstone requires a more powerful pump to generate optimal bubble output. Larger airstones produce more bubbles and work best with strong air pumps. Using a large airstone with a small pump may result in bubbles forming only on the front surface. Small air pumps pair well with small airstones, while powerful pumps are not ideal for small airstones. About shapes: The most common shape is cylindrical, though airstones are also available in spherical, disc, and cube forms. Cylindrical airstones come in various sizes and colors. Disc-shaped stones remain stable at the tank bottom, while spherical shapes tend to produce more uniform bubbles. Note: Measurements are manually taken. Please allow for a 1–17 cm variation. Due to differences in lighting and screen settings, colors may vary slightly. Actual product may differ in appearance.