[scolley]

Thanks for the feedback. Let me try to make combined answers here...

Pressure - There seems to be some valid concern over pressure, or lack thereof, to drive the bubbler. While it might not be enough, I thought the gas leaving the CO2 bubble counter was pressurized, pressure builds up in the CO2 line to the reactor, and once excess gas builds up in the reactor, that gas should be pressurized too. Which means pressurized gas going to the microbubbler.

I neglected to show the typical check valve in the line between the CO2 tanks and the reactor. On mine, the line between the check-valve and the reactor always fills with water when no CO2 is being released. But when it starts, the CO2 drives the water out of the line. And that implies some level of pressure.

Please someone tell me if this is not true.

Water in the line to the microbubbler - That's the check valve I was mentioning. I think that a check valve would keep water out of some of the line, and gas pressure (when the CO2 was back on) would flush the rest. But it could be that 2nd port (gas outflow) needs to be in the top of the reactor for that to work. Which BTW, achieves the same effect as tilting the reactor I believe.

Upside down reactor - unfortunately that will just get bubbles in the tank, not the 100-500 micron tiny variety Tom Barr has indicated is required. That takes an impeller to chop bigger bubbles up, or a diffuser that makes tiny, tiny bubbles as I'm showing here.

Other alternatives - I could just put a "T" on the line coming out of the CO2 tank, and drive the microbubbler with that. Bu then that would require some valves in both lines to balance the CO2 pressure appropriately between both lines after the "T". I was hoping to avoid that complication.

Thanks for your thoughts. If this can be worked out, it could be cool.