BRS CO2 scubber media life

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I literally set up this exact scrubber and media less than a week ago. I bought the recirculating adapter from fish of hex for my reef octopus 200 space saver. I have a 1500 sq ft house, 2 adults, 1 child, and 3 adult great danes, so the co2 levels I’d imagine a pretty high. Living in Indiana there isn’t a lot of weather suitable for open windows…it’s either too hot, too cold, or raining! Prior to adding this to my system my ph never got about 7.8 on a good day. After installing this my ph averages 8.3 in the day time and 8.1 at night. I would say it’s definitely doing it’s job. I will try and keep updating when I have to change the media. I will say I think I’m going to buy another one and plumb inline for a moisture catch because there seems to a lot of it building up in the return line.
 
I literally set up this exact scrubber and media less than a week ago. I bought the recirculating adapter from fish of hex for my reef octopus 200 space saver. I have a 1500 sq ft house, 2 adults, 1 child, and 3 adult great danes, so the co2 levels I’d imagine a pretty high. Living in Indiana there isn’t a lot of weather suitable for open windows…it’s either too hot, too cold, or raining! Prior to adding this to my system my ph never got about 7.8 on a good day. After installing this my ph averages 8.3 in the day time and 8.1 at night. I would say it’s definitely doing it’s job. I will try and keep updating when I have to change the media. I will say I think I’m going to buy another one and plumb inline for a moisture catch because there seems to a lot of it building up in the return line.
How are you oxygen levels. Any concerns based on what randy indicated?
 
In order to prevent over scrubbing, I have installed a bypass line to adjust the ratio of scrubbed and unscrubbed air. This also indirectly introduces some oxygen.

In any case, surface agitation, overflow and sump cascade are all gas exchange surfaces. In many cases, these exchanges is sufficient for oxygenation. In fact, some aquarium may experience ineffective CO2 scrubbing because of these surface exchange in comparison with a under-sized skimmer.
 
So, interestingly, I needed to take my skimmer cup off for the last 24 hours. Since I couldn’t have the input line in the scrubber, I just hung it into the covered section of my sump where my filter floss is. I figured it wouldn’t work as well, but it absolutely did. The scrubber performance really improved when I set it up recirculating for a day and then a day where it was pulling moist air but not recirculated. Both of those days were significantly better. You can see it on my chart. My low last night was 8.0. This makes me think it’s the moisture improving the performance more so the recirculation.

175D7D14-577F-4E11-B8E4-489FF2A8FF8C.png
 
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I run mine as a recirculating scrubber all summer long with no noticeable ill-effects. The fact that it's not just pulling in previously scrubbed air (the lid of the skimmer has a half-dozen holes in it), along with my overflow pulling in air as well as the sump, I'm not concerned about not having enough O2. Fish and corals appear normal, no heavy breathing.
 
Recirc is a big nono…
I mean, maybe for you. A lot of people do it, without any ill effects.
Saw someone with a degree(an actual degree , not a badge on r2r)
Too late to go hunting for it …
Are you trying to say that you saw someone online who claims to have a degree published a whitepaper on their research into recirculating CO2 scrubbers?

Mine lasts a week, obv no recirc
And the bigger the chamber the longer it lasts
This is a false statement. A bigger chamber doesn't make the media last longer. It just gives you more time between media changes. It's still being depleted at the same rate as another sized chamber.
 
I mean, maybe for you. A lot of people do it, without any ill effects.

Are you trying to say that you saw someone online who claims to have a degree published a whitepaper on their research into recirculating CO2 scrubbers?


This is a false statement. A bigger chamber doesn't make the media last longer. It just gives you more time between media changes. It's still being depleted at the same rate as another sized chamber.
Yea i obviously if u have more hp the less u gotta floor the pedal..
Anyways, back to the co2
I listen to “experts”
Not forum fighters
Do as you do!
And btw the media costs for a small hike in ph would get done with cents on the dollar w kalk..
Sooo ‍♂️♂️♂️
 
I run mine as a recirculating scrubber all summer long with no noticeable ill-effects. The fact that it's not just pulling in previously scrubbed air (the lid of the skimmer has a half-dozen holes in it), along with my overflow pulling in air as well as the sump, I'm not concerned about not having enough O2. Fish and corals appear normal, no heavy breathing.

So it is best characterized as a partial air-recirculating skimmer, and your observations related to O2 may not apply to a different setup that is fully recirculating. :)

Do you know what to look for to detect low O2 issues in inverts at night? I do not.
 
So, interestingly, I needed to take my skimmer cup off for the last 24 hours. Since I couldn’t have the input line in the scrubber, I just hung it into the covered section of my sump where my filter floss is. I figured it wouldn’t work as well, but it absolutely did. The scrubber performance really improved when I set it up recirculating for a day and then a day where it was pulling moist air but not recirculated. Both of those days were significantly better. You can see it on my chart. My low last night was 8.0. This makes me think it’s the moisture improving the performance more so the recirculation.

175D7D14-577F-4E11-B8E4-489FF2A8FF8C.png

The issues hare are way more complicated than many folks are assuming.

Folks need to understand, there's no inherent reason that a recirculating skimmer/Co2 scrubber would be better than a nonrecirculating skimmer/CO2 scrubber with the same humidity in the air.

The recirculating version might be better or worse from a media use perspective, and I can show why below.

The critical issue is how much CO2 is in the air returning from the skimmer. Is it higher or lower than the room air? It could easily be either one, depending on how effective the various processes are: how high is the home air CO2, how effective is CO2 exchange with the tank water in the skimmer, and how effective is CO2 reduction by the scrubber, and how low is the tank pH. .

1. If the air returning to the CO2 scrubber has less CO2 than the room air, recirculating will be more effective from a media perspective.

2. If the air returning to the CO2 scrubber has more CO2 than the room air, then media use will be best with nonrecirculating designs.

The decision between whether 1 or 2 applies can certainly depend on:

1. The effectiveness of CO2 exchange in the skimmer, and hence the design of the skimmer (CO2 is hard to exchange)
2. The time of day (impacting CO2 levels in the water and hence CO2 in the return air)
3. CO2 levels in the home air (obviously)
4. CO2 levels in the air coming from the scrubber to the skimmer (lower into the skimmer likely means lower out in the return air)
5. The alkalinity of the aquarium water

In short, when might recirculating be worse? Depends, but here's one example:

At night, when pH is lowest in the tank water (higher CO2). If the skimmer does a good job equilibrating the skimmer air and water, CO2 may be higher in the return air than it is in the home air.

Interestingly, the poorer the skimmer is, the more scenarios there are where recirculating is better.
 
The issues hare are way more complicated than many folks are assuming.

Folks need to understand, there's no inherent reason that a recirculating skimmer/Co2 scrubber would be better than a nonrecirculating skimmer/CO2 scrubber with the same humidity in the air.

The recirculating version might be better or worse from a media use perspective, and I can show why below.

The critical issue is how much CO2 is in the air returning from the skimmer. Is it higher or lower than the room air? It could easily be either one, depending on how effective the various processes are: how high is the home air CO2, how effective is CO2 exchange with the tank water in the skimmer, and how effective is CO2 reduction by the scrubber, and how low is the tank pH. .

1. If the air returning to the CO2 scrubber has less CO2 than the room air, recirculating will be more effective from a media perspective.

2. If the air returning to the CO2 scrubber has more CO2 than the room air, then media use will be best with nonrecirculating designs.

The decision between whether 1 or 2 applies can certainly depend on:

1. The effectiveness of CO2 exchange in the skimmer, and hence the design of the skimmer (CO2 is hard to exchange)
2. The time of day (impacting CO2 levels in the water and hence CO2 in the return air)
3. CO2 levels in the home air (obviously)
4. CO2 levels in the air coming from the scrubber to the skimmer (lower into the skimmer likely means lower out in the return air)
5. The alkalinity of the aquarium water

In short, when might recirculating be worse? Depends, but here's one example:

At night, when pH is lowest in the tank water (higher CO2). If the skimmer does a good job equilibrating the skimmer air and water, CO2 may be higher in the return air than it is in the home air.

Interestingly, the poorer the skimmer is, the more scenarios there are where recirculating is better.
Randy - I know the thought is that recirculating will spare media, but I was surprised to see the increase in ph by both recirculating and drawing moist non-recirculated air. Does this mean I didn’t have enough water in my canister?
 
Randy - I know the thought is that recirculating will spare media, but I was surprised to see the increase in ph by both recirculating and drawing moist non-recirculated air. Does this mean I didn’t have enough water in my canister?

The air in a closed sump may not match the home air, so that may be part of it, but I think the most likely explanation is the cannister didn't humidify the media as effectively. Another possibility is that the resistance to air flow changed and so the skimmer was getting different volumes of air.
 
The air in a closed sump may not match the home air, so that may be part of it, but I think the most likely explanation is the cannister didn't humidify the media as effectively. Another possibility is that the resistance to air flow changed and so the skimmer was getting different volumes of air.
Thanks! I’m just happy it brought it up over 8 for my low value!
 
How are you oxygen levels. Any concerns based on what randy indicated?
I have a rimless 120 tall planet tank, with a custom acrylic/mesh top. I also have icecap 4k gyres at each end causing surface agitation so I’m not very concerned about lack of O2.
 
I have a rimless 120 tall planet tank, with a custom acrylic/mesh top. I also have icecap 4k gyres at each end causing surface agitation so I’m not very concerned about lack of O2.

Almost all reefers say that, and almost all reefers have a pH change day to night that indicates incomplete CO2 exchange. Complete gas equilibration would cause no pH change day to night and pH would only track changes in the home air (and alk, if it did change).

So while it may be true that you have adequate O2 exchange, I do not think that reefers are generally successful at estimating gas exchange simply by looking at the system.
 
Almost all reefers say that, and almost all reefers have a pH change day to night that indicates incomplete CO2 exchange. Complete gas equilibration would cause no pH change day to night and pH would only track changes in the home air (and alk, if it did change).

So while it may be true that you have adequate O2 exchange, I do not think that reefers are generally successful at estimating gas exchange simply by looking at the system.
Speaking of gas exchange, oxygen is not exempted from incomplete exchange with ambient as well. i used to run a dissolve oxygen probe, the water become supersaturated during light hours. The DO level fluctuates as a function of light.

Another huge issue about gas exchange, is that our aquariums are far from perfectly mixed. So depending on the part of the aquarium/sump measured, the result can be significantly different.
 
Speaking of gas exchange, oxygen is not exempted from incomplete exchange with ambient as well. i used to run a dissolve oxygen probe, the water become supersaturated during light hours. The DO level fluctuates as a function of light.

Another huge issue about gas exchange, is that our aquariums are far from perfectly mixed. So depending on the part of the aquarium/sump measured, the result can be significantly different.
Come on @Randy Holmes-Farley , are you going to let him talk to you like that!! GET HIM. Lay the knowledge smack down on him and show him who's the Chemistry king!!

Mothers Day Lol GIF by reactionseditor
 
I guess you just can't provoke as easily a good old chemistry back and forth like you can a tax law debate!!

Chemist #1: My conclusion is "A"
Chemist #2: My conclusion is "A" but stated in my words "a"
Chemist #1: I agree

Tax Guy #1: My conclusion is "A"
Tax Guy #2: My conclusion is "A" but stated in my words "a"
Tax Guy #1: You're "A" idiot!!
 
Almost all reefers say that, and almost all reefers have a pH change day to night that indicates incomplete CO2 exchange. Complete gas equilibration would cause no pH change day to night and pH would only track changes in the home air (and alk, if it did change).

So while it may be true that you have adequate O2 exchange, I do not think that reefers are generally successful at estimating gas exchange simply by looking at the system.
Randy, since oxygen levels are being discussed, and are something we should be aware of, are there any hobby grade monitors for O2 in our tanks?
 

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