# Simple and cheap diffuser



## niko (Jan 28, 2004)

The diffuser itself is made of regular chopsticks - just cut 1/4 (or less) inch of the stick and jam it in the CO2 tubing.










What is important is to adjust the angle and proximity of the diffuser in relation to the water flow shooting downward. In my case I made a small hole on the L-shaped connection of my spray bar, pushed in a small size bendable drinking straw in it, and fiddled with the exact positioning of the diffuser and the water flow "nozzle".

The diffuser itself produces small but not tiny bubbles. When placing it just right by a thin stream of water the bubbles literally get pulverized. In my version no bubble gets back to the surface. They flow down by the back glass and when trying to get back up they get pushed down by the water from the "nozzle".

Jamming the chopstick diffuser directly in the beginning of the spraybar works too. But when the CO2 runs out there will be backpressure that will force water into the CO2 gauge. So I personally prefer to be on the safe side, although water does syphon down to the gauge when the CO2 is off. But at least it's not under pressure.

The design on the picture must be improved using clear glass tubes or acrylic. it can be literally hidden behind the vertical part of the spray bar. And it is easy to visually check if the CO2 is running.

--Nikolay


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## Dewmazz (Sep 6, 2005)

Very nice!


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## david lim (Mar 30, 2004)

I saw this doohickie. It's cheap and produces nice tiny bubbles. Plus it uses chopsticks!

It would seem, though, that would water would still go back down the airline when the CO2 runs out. When you mean "under pressure" do you mean that water isn't forced into the regulator? Maybe it's time to invent a cheap check valve .

David


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## JaySilverman (Jun 19, 2005)

And wouldn't the chop stick dissolve over time?


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## niko (Jan 28, 2004)

David,

If the chopstick part was inserted in the spraybar the pressure from the filter pump will actually force water down the hose when the CO2 runs out. This happens despite the fact that the chopstick does not block the entire flow of the water through the spraybar.

And yes I have to quit being lazy and start putting checkvalves on my CO2 systems. I even got 2 that are metalic and have springs inside laying around.

Jay,

The chopstick would not rot. But it will develop a kind of bacteria that looks like black spots embedded in the wood. That happens with limewood stones used to disperce CO2. It happens in about 3-4 weeks. At that time it's best to just change the chopstick part. Cheap is cheap.

This kind of diffuser works but the downflow of the bubbles seems too unnatural to me... as if something is not right. In addition there is a slight fizzing noize coming from the contraption. I improved the whole design today - it is really compact now and it hides behind the spraybar completely with the exception of less than a 1/4 inch sticking under the bar. I will post pictures when I install it and verify it's working. 

But once again cheap is cheap - I think that a simple glass diffuser is both practical and beautiful.

--Nikolay


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