[Large Bread Air Stone: Size: 6" D x 2" H. Suitable for large aquariums ponds DWC systems and aquaculture farms. NOT fit for small aquariums or fish tanks. Medium Bubbles: The fish tank air stone produces an abundant cascade of dense bubbles. A great way to increase oxygen solubility in your aquarium and enliven the aquatic lives. Steady Output: Jetting volume: 30 L/min; Recommended air pump power: > 20 W; Required airline tubing: 3/16" or 3/8" ID tubing. Efficient bubbler stone for constant air diffusion keeping your fish or roots growing healthily. Stable in Water: The air bubbler is designed with a flat base and weighs 30 oz making it sink to the bottom quickly. It always sits steadily in the water without moving easily when bubbling. Easy to Use: Soak the air stone completely in water for more than 3 hours before use. Clean it regularly with a brush as it gets clogged after weeks or months of usage.]