Best ways to reduce CO2

[lactose]

I have 2 people and 2 large dogs in a 1200 square foot house so CO2 has always been an issue for me.

Here were my fixes in order of greatest effect on pH to lowest effect:
1- Going on vacation (got an Apex notification while on a road trip with my wife & dogs that pH was 8.6!)
2- Recirculating CO2 scrubber (raised pH to 8.2-8.4)
3- Windows open (up to 8.3)
4- Non recirculating CO2 scrubber (up to 8.2)
5- Outdoor air pump line to skimmer with CO2 scrubber (up to 7.9-8.2)
6- Outdoor air pump line without scrubber (up to 8.0)
7- Elevated alkalinity (raised pH ~0.1)
8- Small refugium (raised pH ~0.05-0.1)

It's worth noting for those thinking about a kitchen renovation, a propane stove has a HUGE effect on pH (at least in my small house). After making a full dinner on the stove, pH has dropped as low at 7.4. This was the main benefit of running a recirculating CO2 scrubber on the skimmer. I can cook now without any pH fluctuations.

This is super solid advice. I have a co2 air meter and consistently 1200-1400 in basement with windows closed and seeing high levels with the mindstream now but always knew it from depressed pH.

At one point it made me really sad to realize the best thing we can do for the tank pH is for all of us to leave...

Recirc co2 scrubber plus big refugium on night shift made the biggest difference in past and have the fuge on the system the MS monitor is on so looking to get the scrubber on soon as well.

 

[lactose]

Also with the pH before I could tell when the kids had friends over almost linearly!

 

[rushbattle]

They say 2000 ppm is a concern longer term in a home, 1000 ppm is actually considered good ventilation.

1000ppm is the OSHA limit. It’s pretty easy to argue that 600ppm is the best max target.

Edit: I was wrong, it's the EPA recommends a 1000ppm limit. As does the ASHRAE.

 

[Daniel@R2R]

Best advice: stop breathing so much ;Hilarious

I guess you learned your CO2 levels are high from mindstream? Are you liking it so far?

Yep! It's been great! I already knew my pH was low according to my Apex (typically pH runs low when CO2 is high and vice versa), but the Mindstream registers CO2 levels. That's how I was able to see the problem.

 

[TheHarold]

I anyway knew my pH was running low, but I didn't realize how consistently high my CO2 levels are. I am looking into ways to reduce CO2. What ways have you found to be effective?

I leave the fans on, for my workshop ventilation system. Keeps the PH between 8.1 and 8.4!

 

[Brian_68]

1000ppm is the OSHA limit. It’s pretty easy to argue that 600ppm is the best max target.

The OSHA limit is actually 5000 ppm, not 1000 and if you install a recirc the target inside a home is 1000 ppm for what is considered good ventilation. When the outside approaching 500 ppm or sometimes up to 50% more if located in a city to obtain 600 you would have the windows open constantly or no one at home. Just open a can of soda and the room CO2 jumps considerably......

Permissible Exposure Limits - Annotated Tables | Occupational Safety and Health Administration

www.osha.gov

 

[rushbattle]

The OSHA limit is actually 5000 ppm, not 1000 and if you install a recirc the target inside a home is 1000 ppm for what is considered good ventilation. When the outside approaching 500 ppm or sometimes up to 50% more if located in a city to obtain 600 you would have the windows open constantly or no one at home. Just open a can of soda and the room CO2 jumps considerably......

Permissible Exposure Limits - Annotated Tables | Occupational Safety and Health Administration

www.osha.gov

Right you are, I guess I was thinking of the EPA limit. It's also the ASHRAE recommended limit now that I have looked it up. OSHA regs are short term limits, not for prolonged exposure. I think a ceiling of 1000ppm would be prudent for a household.

 

[Aframereef]

I was having major issues earlier this year. Ph was 7.7. After adding outside air intake to skimmer I got it up to 7.9. Then I sealed off part of my sump and blow air across it from outside, fresh air in moist bad air back outside this brought my ph up to 8.1 and after a few weeks I now run 8.1 to 8.3. I also have always used kalk. Now that its cooling off I opened the house up last night. Ph was 8.5 this morning. Tonight I turned off my sump vent to try to keep it lower. I plan to put the sump vent on a controller.

 

[j0359m]

I never had pH over 7.95-8.0 until I ran a fresh air line to the intake of my skimmer, now it’s 8.2-8.3 depending on time of day

 

[Scott.h]

I never realized how drastic people breathing in a house affected pH until I got an Apex (or 3 lol) . Here in Michigan the weather has been pretty much ideal to leave the windows open this time of year all the time. It takes about two days with the windows open to get my pH up around 8.3 from 7.9ish. Yesterday it was fairly warm out so I closed up the house and turn the air-conditioning on. It dropped to 8.0 in a matter of six hours or so with only me and the dogs here. I also have a gas fireplace that I never turn on - because when I do my pH is drastically impacted within 20 minutes below 7.7.
The simple fact is you can’t do much about it. Would the coral growth be higher if you could? Yep. Will they die if you don’t? Nope. So unless you live in a tropical paradise or have a huge house with a few people in it, it is what it is.

 

[HB AL]

Best thing I did was get the CO2 cannister from BRS with the CO2 scrubbing media. Worked great for me.

Perfect, I just ordered 1 today. My bedroom gets hot facing sun all day so open windows not an option. Have to run ac 24\7 to keep tank below 80 on those summer mornings when there is no marine layer till 11 am.

 

[Daniel@R2R]

I'm also working on bringing my mag back into range. I wonder jf that might impact CO2 levels. I know it impacts pH

 

[bubbasguppies]

I anyway knew my pH was running low, but I didn't realize how consistently high my CO2 levels are. I am looking into ways to reduce CO2. What ways have you found to be effective?

I have opened my windows all day long and that raised it very little. Then I bought a BRS CO2 scrubber with cdex media and attachef it to my skimmer air intake. The media was completely saturated within a months time from only drawing in the indoor air. So I ran a vinyl hose on the input side under the house and then outside. That made a huge difference in my pH values and it stayed steady.

 

[salty joe]

I second this. Kalkwasser is by far the most efficient method.

Kalk would be my first thing to do because it's easy. After that, I'd pull air from outside and if that's not doable use a CO2 scrubber. Kalk and outside air took my pH from 7.67-7.9 to 8 to 8.12 when all the windows are closed. Still not ideal but good enough for me.

Every now and then, we have a big cook and run the oven all day. I have to open a couple windows or the pH drops quite a bit. If I had it to do over again, I definitely would have installed a vent for the stove.

 

[Randy Holmes-Farley]

I'm also working on bringing my mag back into range. I wonder jf that might impact CO2 levels. I know it impacts pH

It shouldn’t.

 

[Dianna Marshall]

I found an article addressing the natural way to raise pH - opening windows, air line from the skimmer, and adding crushed coral. I have had a lower ph than I Would like for a long time, and over the months I’ve added another natural approach to see if it would work. Yes open windows work very well, I have a ceiling fan in the display room, it helps keep air moving, has no effect on pH. Air line from skimmer to the open window - works very well, except for steamy hot humid northeast summers. I had the air line running with a window cracked to allow for the air line and the pH upward movement was negligible.
Cooler days presently and more windows open allowing for natural gas exchange, pH readings moved up, but only to 7.6 to 7.8 over the course of the day. Then yesterday late afternoon I tried adding crushed coral to the rear of my display. I have a 1 inch layer of sand and I approached this ‘science project’ with a wait and see the effects attitude. I prepped the coral - washing it in my home made salt water (fritz pro) and added about 10 pounds. Before sundown, the pH was going up...so ok...but how much? The normal ph at peak for my display is 7.89-7.91. Never getting above that range. By 8 pm - the ph was 8.04 at 7 pm with the lights ramping down. This morning the ph reads 7.92, well above the previous morning readings. I’m not looking for a high spike and I’m happy with the pH range now. Will see how this progresses and try to keep it natural. Display is a RSR 450xl. Hopefully the ph range will establish a new normal, I have one stick in my display that has not done much, so I will watch to see if the ph improves it’s growth.

 

[Dkeller_nc]

Daniel - You don't mention in this thread how many tanks you're trying to correct. Your signature line mentions a 50g Reef Savvy cube. If that's the only tank that you have, installing a heat recovery ventilator to lower CO2 levels in your home may not be so attractive because of the cost. If, on the other hand, you've multiple tanks that all contain SPS corals, it may be the only practical way to deal with the problem over the whole house.

If the 50g is your only tank (or the only tank where pH really matters), I'd strongly suggest installing an outdoor air pump, and plumbing the line from the pump to your skimmer intake. By "outdoor air pump", I mean something modest and inexpensive - a $10 tetra would do the trick. The reason for doing this instead of just running an air line from your skimmer intake outdoors is that depending on the skimmer, the diameter of the airline and the length of the run, there can be enough of a restriction to starve the skimmer of air to some extent. Pressurizing the intake ensures that this isn't the case.

 

[Randy Holmes-Farley]

I found an article addressing the natural way to raise pH - opening windows, air line from the skimmer, and adding crushed coral. I have had a lower ph than I Would like for a long time, and over the months I’ve added another natural approach to see if it would work. Yes open windows work very well, I have a ceiling fan in the display room, it helps keep air moving, has no effect on pH. Air line from skimmer to the open window - works very well, except for steamy hot humid northeast summers. I had the air line running with a window cracked to allow for the air line and the pH upward movement was negligible.
Cooler days presently and more windows open allowing for natural gas exchange, pH readings moved up, but only to 7.6 to 7.8 over the course of the day. Then yesterday late afternoon I tried adding crushed coral to the rear of my display. I have a 1 inch layer of sand and I approached this ‘science project’ with a wait and see the effects attitude. I prepped the coral - washing it in my home made salt water (fritz pro) and added about 10 pounds. Before sundown, the pH was going up...so ok...but how much? The normal ph at peak for my display is 7.89-7.91. Never getting above that range. By 8 pm - the ph was 8.04 at 7 pm with the lights ramping down. This morning the ph reads 7.92, well above the previous morning readings. I’m not looking for a high spike and I’m happy with the pH range now. Will see how this progresses and try to keep it natural. Display is a RSR 450xl. Hopefully the ph range will establish a new normal, I have one stick in my display that has not done much, so I will watch to see if the ph improves it’s growth.

Adding crushed coral will not help the pH unless it is so low that coral skeletons are dissolving already.

 

[Daniel@R2R]

It shouldn’t.

Oh ok. I read recently that really low levels of Mg would cause instability in pH. Perhaps I misunderstood.

 

[Randy Holmes-Farley]

Oh ok. I read recently that really low levels of Mg would cause instability in pH. Perhaps I misunderstood.

More likely, they misunderstood they impact of it reducing the precipitation of calcium carbonate. I’ve seen the inaccurate comment about pH before.