Ultra-high Dissolution: This Nano bubble stone improves oxygen dissolution and reduces carbon dioxide, promoting better respiration for your fish. Its very high dissolution air bubbles are smaller, denser and more uniform. Ultra-quiet: The operating noise in water is very low, it does not affect the normal activities of aquatic organisms and does not disturb children's sleep. Adjustable: You can change the bubble size by hand and let the bubble stone return to the water when all accessories are connected, which can quickly achieve a refining effect. Easy to To use : The ultra-quiet nano aquarium bubble stone can stay in the aquarium without moving, soak in the aquarium for two hours before using the best nano-quiet aquarium bubble stone. Specification of the product : 50mm nano bubble stone*1, suitable for 20-30CM aquarium, the bubble stone is placed below the aquarium.