Pressurized CO2 and declining bubble count?

[Barliman]

Hi all,

I'm new to the world of pressurized CO2 and need some advice.

Yesterday I set up a paintball CO2 system with the following configuration:

24 oz. jar (Amazon)
Paintball regulator with solenoid (GLA)
Bubble counter (GLA)
Tubing (GLA)
Drop-checker (GLA/Cal Aqua)
Diffuser (Some Chinese glass one from my LFS)

Following the directions and the advice from GLA (very fast responders), I set the working pressure to 10 PSI and a bubble count of one bubble every 1-2 seconds as a start. But I've run into a problem...

The bubble count keeps going down fairly rapidly. For example, I set it to 1 bubble per second (Boy, are those needle valves sensitive), but then the bubble rate declines to one every few seconds over about a half hour. (The output pressure seems to stay steady at 8 after setting the bubble rate.)

Is this normal breaking in/adjusting, or is it indicative of a problem, such as a leak? If a leak, where might it be? The regulator or the input to the bubble counter? This doesn't feel like a leak to me, though.

Anyway, I've shut it off for the night. (It's on a timer, but I don't want it running while I'm away at work until I get this sorted out.) Any help or advice is appreciated.

 

[Brookster123]

If it's a ceramic disc diffuser youll want the working pressure closer to 30 psi.

 

[Barliman]

If it's a ceramic disc diffuser youll want the working pressure closer to 30 psi.

Thanks for the reply. That's just the kind: an inverted bell with a ceramic disc. But now I'm confused (not an unusual state):

I wrote GLA and told them I had an off-the-shelf glass diffuser, and they wrote back saying the working pressure should be 5-10. I had originally set it to 30, don't recall if the bubble count declined then.

But, the type of diffuser shouldn't matter to the bubble rate in the bubble counter, should it?

 

[Fresh2o]

I was wrestling with this myself after refilling the tank the other day. I raised the working pressure from 30 to 40 psi. My diffuser is about 7 months old so it may be slowly clogging.

 

[brendenscott]

Maybe they mistook you for saying reactor and not diffuser. Reactors are fine at that low of working pressure. Diffusers you need higher. Typically 30 psi.

 

[Barliman]

Thanks for the advice. I'm going to try again with a higher pressure. But, to be clear, the problem is not in the diffuser: I'm concerned about the declining bubble rate in the *bubble counter*, itself, before the gas ever gets to the diffuser.

 

[Caliban07]

The diffusers have a working pressure of around 30PSI. The pressure output from the regulator will build up against the back of diffuser and once the working pressure is attained the gas will begin to flow through the diffuser.

As I understand it, if you have a lower working pressure 10psi it will eventually build up to the diffuser working pressure 30psi when the needle valve is open. The pressure will build up faster the more you open the needle valve. When the 30psi is achieved at the diffuser you will see some gas flow in the form of a bubble and a bit of diffused co2 gas (tiny bubbles) but at this point the pressure drops and has to be built up again before you get the next bubble.

The diffuser is like a gate that is being pushed open by water. You want enough water to ensure that the gate remains open all the time.

 

[Funken_A]

If you like a DIY project I HIGHLY recommend building a reactor instead of using a ceramic disc diffuser.

Here's my tutorial on a Cerges reactor I built that acts like a 2nd filtration device as well as CO2 reactor. AND adds more water flow throughout my tank which is very important for planted aquariums


http://www.aquariumadvice.com/forums/f20/diy-cerges-co2-reactor-biofilter-357263.html



much better way and worth the time and investment

 

[Barliman]

Thanks for the advice folks. I determined the problem had to be somewhere on the path from the regulator to the bubble counter, so I reseated the tubing and that solved the problem: I have a nice, steady 1 bubble per second, now.

Now, of course, there's a new problem. I can *hear* a leak (sounds like a faintly trilling bird), which I figure has to be on the path from the bubble counter to the diffuser, which means either the counter itself, or the tubing.

Time for the soapy water.

Thanks again!