Purging CO2 from tiny fish room

[Tuffloud1]

I have a linen closet that I converted to an in-wall tank (see my build thread for details).

I have a bathroom ventilation fan in the ceiling that goes through the attic and to the outside. This keeps moisture down which would otherwise be a major issue with water dripping down the walls.

CO2 has become an issue even with this ventilation fan because it’s pulling CO2 from the rest of the house which passes through this little room and then out through the fan.

I had the idea to install an identical fan except instead of pulling air out of the room, it would pull air from the outside into the room through the ceiling next to the other fan that is removing air.

It seems this would eliminate the issue of having to open windows in the rest of the house when the outside temperature is undesirable.

Would this be effective in purging CO2? I understand “fresh air “ isn’t the issue with CO2 reduction. What I need to do is remove the CO2.

Correct me if I’m wrong but it is my understating that a large percentage of CO2 in the air will sink lower than O2.

With the inlet fan and outlet fan being in the ceiling in a tiny room directly above the tank (about 3.5 feet), and pushing an equal amount of volume in/out between the 2 fans, would this be effective at purging CO2 from the room? My concern is that the CO2 will sink and incoming fresh air will get trapped at the ceiling and just go straight out the exhaust fan.

Would this be more effective than running outside air to the skimmer?

 

[Pistondog]

Tough one.
What if you pulled a small amount of air from outside into the closet and let the humidity flow into the rest of the apartment?
Dispersed, it may not be detrimental. One of the benefits to me of 3 tanks is more humid air in winter.
Maybe just run the skimmer air intake outside as an experiment.
If you pull larger amounts into the closet, the closet temp will approach outside temp.

 

[00W]

Very interesting.
Like a restaurant hood fan that takes exhaust out, I have to run make up air in my commercial kitchen unless I want to get ill from lack of oxygen.
In essence, this is your idea.
Will it work/help? Yes. But, in your case due to room size, you have to be careful and either baffle the makeup air or run a stronger fan for inlet air than exhaust air or put the inlet air in a different spot.
So if you put both of them next to each other in the ceiling, say, it's not going to be as effective as say directing the makeup air away from the vent and/or installing the vent lower.
The stronger the makeup air is the more effective.
To get very creative you can put them on timers or switches and run them when you want.
My two tanks are in a smallish room downstairs. I have lots of problems in the winter with PH and exhaust from the stove inside.
During the summer I open the windows and bam PH is where I want it to be.
I made a homemade scrubber and it helped a lot. Nothing like fresh air though.
If you run your skimmer air line outside that would work also but it may not be a totally viable option for you.
Just some thoughts.
Hope that helps.
Joel

 

[Righteous]

Just have everyone hold their breath.

I think you’re going to find that a line to the skimmer is going to be more effective. You’re guaranteeing the air exchange in that case. I know from trying to vent server rooms, sometimes airflow in large spaces can get tricky.

I always advise a simple CO2 scrubber first. It’s incredibly efficient, and cheaper than installing vents and fans etc, even counting the media. My first was made from an old gallon water jug... just dremel some thin holes in the bottom for air flow and fill with media. If you get tired of changing media one a month or so, then maybe tackle more complex air exchange.

 

[Randy Holmes-Farley]

I have a linen closet that I converted to an in-wall tank (see my build thread for details).

I have a bathroom ventilation fan in the ceiling that goes through the attic and to the outside. This keeps moisture down which would otherwise be a major issue with water dripping down the walls.

CO2 has become an issue even with this ventilation fan because it’s pulling CO2 from the rest of the house which passes through this little room and then out through the fan.

I had the idea to install an identical fan except instead of pulling air out of the room, it would pull air from the outside into the room through the ceiling next to the other fan that is removing air.

It seems this would eliminate the issue of having to open windows in the rest of the house when the outside temperature is undesirable.

Would this be effective in purging CO2? I understand “fresh air “ isn’t the issue with CO2 reduction. What I need to do is remove the CO2.

Correct me if I’m wrong but it is my understating that a large percentage of CO2 in the air will sink lower than O2.

With the inlet fan and outlet fan being in the ceiling in a tiny room directly above the tank (about 3.5 feet), and pushing an equal amount of volume in/out between the 2 fans, would this be effective at purging CO2 from the room? My concern is that the CO2 will sink and incoming fresh air will get trapped at the ceiling and just go straight out the exhaust fan.

Would this be more effective than running outside air to the skimmer?

That reverse fan will solve the issue. of course, you do not want to pull in excessively hot or cold air.

 

[Tuffloud1]

I decided on going with one of these -

FV-04VE1 - Panasonic FV-04VE1 - WhisperComfort 40/20 or 20/10 CFM Ceiling Spot Energy Recovery Ventilator

Panasonic FV-04VE1 - WhisperComfort 40/20 or 20/10 CFM Ceiling Spot Energy Recovery Ventilator - <b>Overview</b><br> Panasonic WhisperComfort Spot Energy Recovery Ventilator (ERV) offers a revolutionary way to provide balanced venilatiuon with a ceiling insert ERV. Affordable and easy to...

www.supplyhouse.com

 

[Randy Holmes-Farley]

Looks good.

Let us know what you find.

 

[Tuffloud1]

Thanks for all the ideas, thoughts everyone.