CO2 Spray Bar - a summary

  • Thread starter Thread starter Yugang
  • Start date Start date
  • Tagged users Tagged users None
Sure, @Koan, but these are Canadian sites. You can probably find the same things in the US, only cheaper!

Transparent tubes: Rebower 14" Clear Plastic Rigid Pipe
End caps: uxcell 1Pcs Pipe End Cap Fitting
Silicon plugs: Silicone Rubber Tapered Plug Assortment
(I find a lot of uses for these!)

I used thin CA glue to attach the end caps and regular 1/4” Co2 tubing jammed into a slightly smaller hole. Regular old black zip ties to attach.
The key was having somebody else do the cutting - I would have made a huge mess : )
 
Last edited:
That looks fantastic! Great work!

I think we're in agreement that Ci has officially cracked the attractiveness code for this new reactor approach
😁💯🏆🎉🎉

1000035906.jpg
1000035907.jpg
1000035908.jpg

Just like Aqua Rocks Colorado did with their stainless version of the first Yugang reactor ! 👍👍👍

So in the interest of supporting wider adoption for this new tool, can I request we now talk about a rebranding?

The "spray bar" filter return is not a tool that's widely used in high-end planted aquariums. Quite the opposite, the term calls up images of gunky, clumsy, BBA infested pinhole tubes made out of black or Eheim-green plastic .

1000035903.jpg1000035904.jpg

Pretty much exactly counter to the open clean rimless aquarium aesthetic.

It is not a name that can immediately attract interest or make someone want to investigate further, let alone commercialize.

Also, this device is not actually a filter return!

What if we started calling it the "Yugang Open Reactor" instead?

🤔
 
Last edited:
Black furniture grade glossy PVC I think blends in nicely with a black background 👍🏻 but of course I’m partial since it’s how I’m setup 🤪 I have made the spray bar work for me with holes on both sides to get as much flow as I can throughout the tank.

I have to agree, that clear setup is gorgeous.
 
In some private correspondence with @Yugang, he determined that my “68g with a 40”x 17” surface area = 438.709 mm2 surface area. Divided by 17.7 gives 24.785 mm2 for the CO2 Spray Bar. If we would use a 1 inch diameter tube, we would need it to be 976 mm long to have that surface area.
This calculation is for about 1.5 pH drop. What we know is that 0.3 pH drop corresponds to a factor of 2 in CO2 ppm, therefore for an estimated 1.2 pH drop we could do with 976/2 = 488 length of the 1 inch tube.”

To simplify:

For a 1.5 pH drop I need a 1”x 38” (976mm) tube.
For a 1.2 pH drop I would halve that to 19” (488mm)
For a 0.9 pH drop I can halve it again to 9.5” (244mm)
With 2 days of testing behind me, it is clear that my 14” (I mentioned 12” previously, but it is 14) reactor is giving me an almost exact 1 pt. drop in pH, which is just where I hoped it would be.
Very pleased with the outcome of this project!
 
The name "Open Flow Reactor" was suggested, and indeed that seems to fit better than my original name CO2 Spray Bar.
 
I received a couple of questions how CO2 Spray Bar / Open flow reactor compares to the old CO2 bell.

Fundamental feature of CO2 Spray Bar is the overflow. Other than a CO2 bell, the CO2 Spray Bar has a constant GEOMETRY, gas pocket always same volume so that the water/gas interface is always same and will not change with CO2 being consumed.

Then, because the overflow purges impurities from the CO2 gas pocket, we can assure a constant PURITY of the gas pocket, also this is different from the old school CO2 method.


When both GEOMETRY and PURITY are stable, then we can be sure that CO2 INJECTION rate is stable. This rate of injection cannot be calculated from equilibrium values (Henry's law) as it is essentially a flow because we have NO equilibrium and the system wants to move towards equilibrium. This is why we use the same calculation principles as for the Horizontal Reactor / Yugang Reactor , ie a 17.7 ratio for a 1.5 pH drop and about 35 ratio for an estimated 1.2 pH drop, while for a traditional CO2 Bell we won't have a constant injection rate and it is not possible to have a precise calculated size and pH drop.

I hope this helps to clarify
 
I am posting here to address a common misunderstanding regarding gases at room temperature, where it is thought that the heavier gas CO2 will accumulate at the bottom of a gas pocket. This was mentioned to me in a PM, in the context of the purging of gas in CO2 Spray Bar and Yugang reactor , but I also saw it mentioned at UKAPS.

Indeed, at very low temperatures gas molecules are hardly moving and in this case the heavier gases will accumulate at the bottom while light gases are mostly found in the higher layers.

However, at room temperature molecules move fast and heavier and less heavy gases will mix. For any significant concentration differences we would consider hundreds of meters, if not kilometres in the vertical direction, but certainly not centimetres or decimetres. This means that gas purging from the reactor will represent same mix of CO2 and other gases as anywhere else in that small gas pocket. It would be a misunderstanding to claim that CO2 would accumulate low in the reactors gas pocket, at room temperature as it is thought to be heavier than other gases.

And for UKAPS readers - CO2 will not accumulate just above the water in a tank, as it is thought to be heavy and would prefer not to diffuse into the ambients air. A mouse on your bedroom floor will not suffocate in the CO2 that you exhaled.
 
I am posting here to address a common misunderstanding regarding gases at room temperature, where it is thought that the heavier gas CO2 will accumulate at the bottom of a gas pocket.
Attached paper reports CO2 concentration in the atmosphere. From figure 10 we see that concentration varies by less than 3% over 5 kilometres of elevation. Note these are relative concentrations in % or ppm, CO2 compared to other gases. Proximity to a CO2 source is more relevant than relative weight of gases. This is to say that this weight consideration is irrelevant for our tanks, or purging in a horizontal reactor.

Not correct, #10, as per the above.
Another common mistake (from PM's I received as well as this thread on UKAPS) is to assume that Henry's law tells us the rate of outgassing, while the reality is that Henry's law describes equilibrium when indeed gas concentrations are stable and flows balanced to nett zero. The rate of outgassing cannot be derived from Henry's law, only that gas flows are nett zero when Henry's law applies.
 

Attachments

Last edited:

Top 10 Trending Threads

Back
Top