Check the listing for details. Large Air Stones Cylinder Bubble Diffuser Aerator Aquarium Air Pump Hydroponic. Condition: New. Listed at 14.99 USD. Large Air Stones Cylinder Bubble Diffuser Aerator for Aquarium Fish Tank Pump Hydroponic Oxygen Plate Mini Air Pump Feature: 1. Medium Bubbles: With lots of micro holes which allow abundant dense and even bubbles to spout from the cylinder. An ideal way to fully aerate your water tanks. 2. Larger Size: 8 Inch Measure 2" D x 8" L. Fit for large reservoirs like ponds, gardens, some large aquariums or DWC systems. NOT suitable for small fish tanks. 3. Stable in Water: Weigh 16 oz and come with 2 square holders at both ends to increase stability. It always lies steadily in the water without moving easily when bubbling. 4. Easy to Use: Soak it 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. Specifications: Model: 4inch; Jetting volume: 18L/min; Recommended air pump power: > 7 W; Standard ID airline tubing: 3/16" or 3/8". Keep fish or roots growing healthily. Model: 8inch; Jetting volume: 24 L/min; Recommended air pump power: > 7 W; Standard ID airline tubing: 3/16" or 3/8". Keep fish or roots growing healthily. Model: 12inch;etting volume: 30 L/min; Recommended air pump power: > 7 W. Standard ID airline tubing: 3/16" or 3/8". Keep fish or roots growing healthily. Note: -Soak in water for 15 minutes before use. -For long-term use, if there isdirt blockage, and the bubbles is reduced, please take itout of the fish tank and wash itagain and again. -The air stone can be used repeatedly. -Please allow 1cm differs due to manual measurement. -Due to the different display and different light, the picture maybe a little different withthe actual color of the item. Thanks for your understanding. Package:1pcs Aquarium Fish Tank Air Stone