Fine Bubbles: The air stone disc produces lots of dense medium bubbles. A great way to oxygenate your hydroponic growing systems, ponds, aquariums and enliven the aquatic life. jetting volume: 12 L / min; recommended air pump power: > 4 W; standard ID airline tubing: 4 mm. Durable Material: Made of mineral material and sintered at a high temperature. Great for aeration in a DWC reservoir. Help keep fish / roots growing healthy. wer: 4W-8W. Stable in Water: weighs 198g. 3 strong suction cups easily fix it in the smooth aquarium, allowing it to lie steadily in the tank.Stable in Water. Easy to Use: Soak the stone completely in water for 1 hour before use. Clean it regularly with a brush as they get cl ogged after weeks or months of usage. the smooth aquarium. Delivery Quantity: 1pcs Product color: black Product size: 10.8*1.9cm