You can test your old stones by blowing through the tubing. You shouldn't have much resistance.
You can soak the stones in vinegar to clean them. But you really don't need them to mix.
If it is also for oxygenation then maximum surface turbulance is what you want. Oxygen enters water by gas exchange through surface turbulence not by being injected through a stone. Nothing happens until the bubbles break the surface.
You can soak the stones in vinegar to clean them. But you really don't need them to mix.
If it is also for oxygenation then maximum surface turbulance is what you want. Oxygen enters water by gas exchange through surface turbulence not by being injected through a stone. Nothing happens until the bubbles break the surface.