I wonder if you could make it work with those ultra-fine diffuser stones used to directly oxygenate big fish transportation tanks. The super tiny bubbles would have greater gas exchange at a lower air volume. Additionally they would move the water MUCH slower, which is one main reason they are not used in ordinary pond diffuser systems.
I have heard those clog easily. I plan to use a vertex diffuser as I have one. I will be running around 1cfm through it.
This will be a hack job for sure and I wont know if it worked until this time next year. Can't hurt to try.
