Seriously ??? I was playing with a venturi design using a mixing condenser prior to the reactor, and it relegated the reactor to a fairly useless state (Pretty much eliminated it) There was a slight affluent of micro bubbles, but not nearly enough to justify the reactor tube. IMHO just enough to compliment the plants.

The design required significant pressure. So I'm back tracking to the gas injection port to better accomodate Co2 at a lower flow rate suitable for powerhead applications.

It was easy to build an industrial model. The trick will be in accomodating lower head pressure suitable for smaller aquariums. Every design I've seen no matter how efficient has a feeble venturi, and the port was designed for O2. Drafting the intake prior to the impeller is only half right. Your diagram (90* Shear to the intake, and description of the tapered tubing is well on the right track, but a few accomodations for a proper venturi, and swirl might add 30 or 40% increase in volume, and saturation. I'll be sure and post plenty of diagrams right away so someone can relable it for production ! LOL.

I think my brain is finally wrapping itself around this better! It is the high speed of the water through the venturi throat that make it work so well? The rapidly flowing water rips the little CO2 bubbles apart as they squeeze out thru the orifice? That makes a lot of sense. Then as the flow slows downstream, the pressure rises, which shrinks the bubbles even more? If I have it right, the best location to inject the CO2 would be the venturi throat, where the velocity of the water is the highest. And the smaller the inlet orifice for the CO2, the smaller the entering CO2 bubble , making the shredded bubble the smallest.

Thanks for stimulating my mind with this!! Now I can visualize ways to use this effectively.

Got It ! Using the tapered pipette the inlet doesn't have to be offset. I just have to decrease the diameter of the opposing pressure well to the same diameter of the pipette, and keep the inlett slightly proud of the throat.

The use of the needle wheel impeller is even better, producing a much finer cavitation, and the ceramic bearings are a huge perk !

For a 1/2" flow the mixing chamber should be appx. 4 " long. Maybe 5" tops.

If the swirling veins are in the venturi, and the affluent is compressed. The reactor is eliminated...

But even with a reactor, there is a pressure drop like with this, it's just smaller and easier to make.

A nice venturi would be a good CO2 device though, it would get the disc out of the tank and do the same type of thing.

Reactors are designed to get the CO2 100% dissolved, disc sort of do that unless you blast the bubbles around.

Why have a disc and a filter doing this when a venturi in line with the filter can?

Regards,
Tom Barr

For the time being I eliminated the tapered pipette, and am using capillary tubes to modify the gas intake. This allows me precise metering of the gas, and permits me to adjust the height of the leading edge within the throat to increase or decrease shear pressure across the intake.

Cap tubes can be used very simply, but be careful, such fine micro tubing can break if too much gas is added.
Regards,
Tom Barr

I had to cut these to length with a 400,000 rpm disc ! Tweren't EZ !!! LOL. But now they're "Custom Parts"

FTR they're sheethed by a 1/8" polypropylene bulkhead.

Any Pics of your project?

None yet Peter, I'm working with multiple formats at the moment. It's unlikely I'd post pics to the web just yet, but I have a few friends in Sweden capable of the fabrication. Where are you at in Sweden ?

I can try to translate to Swedish if you like. It may not help with the description, but it's sure to provide some comedy relief !

If you can tell me the diameter of the tubing I can calculate the tapers for you. Grtz. Prof M

If you mean my tubes i did ?

well the diameter inside of tube
1. is 21mm and in the middel(thin part of the tube) it 8mm

2. is 17mm and in the middel(thin part of the tube) is 6mm

Or you better translate in to swedish

Im located in the south part of sweden close to Malmoe.