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I've learned from the forum over the years that airstones are not needed, esp if you have a HOB filter.
But if you like the look of bubbles I always just bought the cheapo cardboard type wands so they can be easily replaced every year or so and made sure to anchor the air hose to something. For example twisty tie it to the power chord of my heater so it doesn't get jerked around. I also made sure not to disturb it much when fussing/cleaning the tank.
Nothing lasted particularly better when buried. For me anyhow...
Shrimp and snail junkie... What can I say, I like the little things in life.