Welcome to ShenMo shop! Medium bubbles: With lots of micro-holes which allow abundant dense and even bubbles to squirt out of the cylinder. A perfect way to completely aerate your water tanks. Larger size: measures 5 D x 20 L (cm). Suitable for large tanks like ponds, gardens, some large aquariums or DWC systems. NOT suitable for small aquariums. Model: ASC200; Spray volume: 24 L/min; Recommended air pump power: > 7W; Standard ID Aircraft Tube: 4 or 8mm. Keep fish or roots growing healthy. Stable in water: Weighs 454g and comes with 2 square supports at both ends to increase stability. It always remains stable in the water without moving easily when it bubbles. Easy to use: Soak it completely in water for more than 3 hours before use. Clean it regularly with a brush because it clogs after weeks or months of use. Due to manual measurement, the products you receive may have some dimensional errors Due to different monitors, the products you receive may be slightly different from the pictures Actual delivery quantity: 1 piece 100% satisfaction - Our customers are our priority. If you find any problems with the products after receiving the goods, such as damage and incorrect quantity, please contact us immediately. We do our best to provide you with satisfactory after-sales service.