For me, this air stone is now in use for 2 years. The air channels have become more concerned with the time, now it is bubbling in many places with tiny bubbles and looks nice. I have him. In a group with several lava Visually I like it better than the typical air vents, and the bubbles are better distributed. Also, I must not replace it because it does not become clogged.
A star deduction because of something cheap processing of the air connection, be careful here when connecting the hose, so that nothing breaks. Floating is no longer a problem when it has soaked for now. Before inserting one should wash him anyway.