Medium bubbles: The air stone produces dense and abundant bubbles to aerate your water tanks. A great way to increase oxygen solubility in aquariums, fish tanks or ponds. Recommended air pump power: > 4W; Standard ID Air Hose: 0.4cm or 0.8cm. Ideal for aquariums, DWC systems or ponds. Reliable Material: Made of mineral material and sintered at high temperature, it has no effect on the health of your aquatics. Helps maintain healthy fish or root growth. More Float: Measures 10D x 7.4H (cm). And its wide, flat bottom always keeps it stable in the tank to produce more stable bubbles. Easy to use: completely soak the stone in water for more than 3 hours before use. Clean it regularly with a brush as it clogs after weeks or months of use. Specifications: 10cm diameter, can be connected to 4mm or 8mm trachea Color as shown Quantity delivered: 1 piece