[SingAlongWithTsing]

So I've set up a CO2 system about 2 weeks ago and I've been noticing an air pocket develops at the top (around the top 3") of my rex reactor by the end of the day everyday.

Would drilling a hole at the top and sticking an air line tube in it and running the other end of the tube to my water pump's intake solve this problem?

 

[benealing]

That would likely solve the problem, you could also just dump it back into the tank directly. Why does the bubble concern you? My rex reactor also forms a bubble, but it is gone a few hours after the CO2 turns off.

Alternatively, you could try to adjust the reactor to increase the flow. What really helped mine was to place a piece of bamboo into the CO2 line right where it enters the reactor. This makes lots of small bubbles rather than one large bubble at time. This improved the efficiency of my CO2 dissolution.

Ben

 

[Seetide]

Don't know if you have room for a tiny pump in yours, might look at the design on the Carbon Doser EXT 5000, has a tiny pump in bottom that mixes almost 100% of co2 in the reactor.

 

[josephla]

forgive me for my ignorance in advance...
how do you know that you're getting an air pocket inside of your reactor without it being completely transparent? bubbles? noise? what's the indicator?
i've used a rex reactor previously and use one currently and i've never even thought about an air bubble forming at the top nor has anything ever given me the idea that there would be one.
i have maybe 8-9" of tubing between the outlet of my filter to the inlet of my reactor, and the reactor itself is Ø 1.5" x ~20". i use a drop checker for approximate co2 levels and it's always green so i haven't worried about losing any co2 what so ever. rarely are there bubbles coming from my outlet into the tank, so i've been under the impression that almost 100% of my co2 is being dissolved as well.
now you guys have my gears turning.

 

[benealing]

I can hear the water gurgling at the top of the reactor. It has never bothered me. As long as I am not getting CO2 bubbles coming through my spray bar and my plants are growing, I am happy

Ben

 

[sohankpatel]

I have a bubble in mine by the end of the day as well, i can hear it gurgle. I have no issues with it as it is gone quickly. Try putting an airstone at the end of the co2 line to break up the bubbles.

 

[josephla]

okay, 2 points to gurgling. i guess i'm doing something right as i've never ever heard mine gurgle - not now, not 9 years ago. :hihi:

 

[aja31]

As long as you put the other end of the tube into a lower pressure area it will get sucked out via the venturi effect. It can either be the air or into a higher velocity tube (i.e the pump intake/output). This is a good way to reduce noise if it bothers you. If the noise isn't an issue then you don't really need to do anything. The CO2 is still in direct contact with the water running by it, so you will still get 100% diffusion into the water.

 

[alberth]

You can actually install a bleeder if too much air accumulates which usually happens after water changes. Most commercial CO2 reactors actually have air bleeders. You can install tubing on top of the reactor and use a pipe valve like this

that you can unscrew open to bleed off trapped air. Just install an airline tubing in the pipe valve output that goes back to your tank.

 

[SingAlongWithTsing]

forgive me for my ignorance in advance...
how do you know that you're getting an air pocket inside of your reactor without it being completely transparent? bubbles? noise? what's the indicator?

i'm using clear pvc for the main body.

As long as you put the other end of the tube into a lower pressure area it will get sucked out via the venturi effect. It can either be the air or into a higher velocity tube (i.e the pump intake/output). This is a good way to reduce noise if it bothers you. If the noise isn't an issue then you don't really need to do anything. The CO2 is still in direct contact with the water running by it, so you will still get 100% diffusion into the water.

yeah decided to drill a 3/16" hole and stuck a 1/4" air tube in it and used loctite gel super glue to seal it just incase. stuck the other end to the the pump intake.

 

[nilocg]

Is there a reason other than noise that this concerns you?

 

[josephla]

would another way to solve this problem simply be connecting airline tubing (green) from the top area where the trapped co2/air is (grey), to the bottom of the reactor as to pull it out?

see attachment

 

[SingAlongWithTsing]

Is there a reason other than noise that this concerns you?

wouldn't the air pocket slow down the flow even further? if not, i wasted my time drilling and stabbing a tube in it lmao

 

[benealing]

@josephla If you do it that way, the CO2 will just be pushed out into the tank without dissolving and would cause some air bubbles in the tank. I suppose the end result is the same either way the CO2 gets evacuated. I just don't like to see the air bubbles into the tank and would prefer to have as few holes as possible in my reactor (less leaks).
@SingAlongWithTsing I have not noticed any slow in flow with an air pocket at the top.

Ben

 

[josephla]

@josephla If you do it that way, the CO2 will just be pushed out into the tank without dissolving and would cause some air bubbles in the tank. I suppose the end result is the same either way the CO2 gets evacuated. I just don't like to see the air bubbles into the tank and would prefer to have as few holes as possible in my reactor (less leaks).

in my co2 reactor I have tons of ceramic media to dissolve it. i bet if i were to connect it maybe an inch or 2 below the original co2 inlet, it would do a much better job dissolving it before it gets out, than connecting it close to the outlet of the reactor. and a shorter length of tubing would probably mean more suction strength of the air at the top?

 

[nilocg]

wouldn't the air pocket slow down the flow even further? if not, i wasted my time drilling and stabbing a tube in it lmao

No I really do not think that it would slow down flow