CO2 Reactor Air pocket

[nijat11]

Hello everyone!
I have a problem with my co2 reactor. Here is my setup:
I have separate 2000l/h pump connected to aquamedic reactor and located in the 3rd chamber of sump, outflow from the reactor goes to 4th chamber of sump next to return pump.
During the day I get air pockets and need to open valve to release it, so reactor can be filled with water. My quesiton is, can I connect small hose to valve, put it in the sump and leave open permanently ? Will it increase co2 usage?

 

[LMuhlen]

If you leave the gas pocket, does it keep increasing until the reactor colapses, or does it form an equilibrium in which the pocket stops increasing and no bubbles escape the reactor?

If the gas pocket leads to a colapse, then it sounds like you are trying to inject more CO2 than your reactor can handle. You would need to find a way to modify it or inject less CO2. Adding a permanent purge sounds like a waste of gas, you could just dial it down.

 

[hypnogogia]

During the day I get air pockets and need to open valve to release it, so reactor can be filled with water. My quesiton is, can I connect small hose to valve, put it in the sump and leave open permanently ? Will it increase co2 usage?

Purging the CO2 form the gas pocket means you have lost/waisted the gas. Best not to have the gas bubble develop in the first place.

If you leave the gas pocket, does it keep increasing until the reactor colapses, or does it form an equilibrium in which the pocket stops increasing and no bubbles escape the reactor?

This is the key question though. If it reaches equilibrium, all is fine, if not, then turn down the gas.

 

[nijat11]

If you leave the gas pocket, does it keep increasing until the reactor colapses, or does it form an equilibrium in which the pocket stops increasing and no bubbles escape the reactor?

If the gas pocket leads to a colapse, then it sounds like you are trying to inject more CO2 than your reactor can handle. You would need to find a way to modify it or inject less CO2. Adding a permanent purge sounds like a waste of gas, you could just dial it down.

Purging the CO2 form the gas pocket means you have lost/waisted the gas. Best not to have the gas bubble develop in the first place.


This is the key question though. If it reaches equilibrium, all is fine, if not, then turn down the gas.

Because of sump and big aquarium size, I need huge amount of co2, to understand, I replace 10kg every 2 months. So if decrease the amount of gas, I will not get 1 pH drop. I will say it stops at half of the reactor.
So I was thinking just leave valve open and it will push everyting into the sump water

 

[hypnogogia]

Because of sump and big aquarium size, I need huge amount of co2, to understand, I replace 10kg every 2 months. So if decrease the amount of gas, I will not get 1 pH drop. I will say it stops at half of the reactor.
So I was thinking just leave valve open and it will push everyting into the sump water

If it is stopping half way down the reactor you are reaching equilibrium, where gas absorption rate = gas injection rate.. Opening the valve would waste the gas in the rector and serve no purpose, in my opinion. You'd be better leaving it alone and allowing the bubble to decrease once the gas shuts off over night. If it isn't reaching equilibrium and continue to grow, then you do not need that gas and wouldn't lose anything by reducing the bubble rate slightly.

 

[LMuhlen]

So if decrease the amount of gas, I will not get 1 pH drop.

All this CO2 you are purging isn't being added to the water, so there should be no reduction in dissolved CO2 if you reduce the injection rate just enough to bring the equilibrium of the gas pocket to be reached with a much smaller pocket, maybe even without one. Usually, large gas pockets reduce the effectiveness of the reactor and, when they start growing, it spirals out of control, with an ever growing gas pocket and an ever reducing dilution rate.

CO2 reactors have a limited capacity. It sounds like you need more than it can give, or that you are just at its limit. There are changes that can be made in some reactors to increase their capacity, but maybe you would benefit from a larger one, or even having 2 of them.

 

[nijat11]

What if I will increase flow in the reactor by removing outflow hose and putting it right into the chamber

 

[LMuhlen]

Increasing flow through the reactor will definitely help, up to the limit where bubbles start being dragged out of the reactor undissolved. Still, I think that it is better to have some micro bubbles expelled eventually than have a very large gas pocket form. But ideally you would be somewhere in between those 2 scenarios.

 

[foxfish]

Sound like you need a bigger reactor.

 

[nijat11]

Increasing flow through the reactor will definitely help, up to the limit where bubbles start being dragged out of the reactor undissolved. Still, I think that it is better to have some micro bubbles expelled eventually than have a very large gas pocket form. But ideally you would be somewhere in between those 2 scenarios.

And the last queation, what if I connect attomizer to air valve and keep it open?

 

[LMuhlen]

And the last queation, what if I connect attomizer to air valve and keep it open?

I'm not sure I understand what you are proposing, but atomizers usually require gas pressure, which you don't have in a reactor. If you make any mechanism to purge the excess gas, either manually or automatically, my opinion is that it is better to dial down the injection of gas into the reactor instead. You are working at the maximum capacity of your equipment as it is set and wasting excess gas. Better to keep it at the same maximum capacity without wasting the gas.