hygger Aquarium Air Stone, Bubble Stone Fish Tank Oxygen Ultra Silent Deep Dissolving Oxygen Diffuser Kit for Aquarium Fish Tank and HydroponicAuthor: hygger Brand: hygger Color: Black Features: Fine bubble: Oxygen stone refines the air output from the air pump into a particle bubble, which is smaller and denser, like the atomization effect, and the bubble size can be adjusted, and the different oxygenation amount can satisfy different use requirements High dissolved oxygen rate: Compared with ordinary bubble stone, the nano bubble stone emits more bubbles, and the gas and the water surface