CO2 Scrubber - any problem with this plan?

[ID-Reefer]

My PH seems to average about 7.90. Never getting above 8 and occasionally dropping below 7.85. Thinking its time to try a CO2 Scrubber. Ive never used one in the past and thinking about installing on my new system (Reefer 900 - 243 gal.)

Looking at the large IceCap scrubber which holds 4.4lbs of media. Will install in the cabinet behind my tank in another room which also holds my Trident, ATO tank, UV etc. Makes for easier access and a cleaner sump area. The air line from my skimmer will run about 3-4 feet to the scrubber. Then Ill either draw air from within that cabinet or I can run the supply air to the scrubber from down in the crawl space. I could run the supply tube over to a crawl space vent which would provide outside air but it would be about 10' away. Not sure if thats to far to suck air from.

Thoughts on this set up? Thoughts on taking the air from within a cabinet in another room vs running down through crawl space to an outside vent?

Lastly - suggestions on the best media to use?

Appreciate thoughts/advice.

 

[Dkmoo]

Using outside air could affect ur ph if you live in a cold winter are

Using inside air may be too high in CO2 and burn thru your media quickly.

If either is an important factor in your circumstance I would suggest a recirculating setup and add a DYI moisture trapper to prevent water getting into your scrubber

 

[ID-Reefer]

Using outside air could affect ur ph if you live in a cold winter are

Using inside air may be too high in CO2 and burn thru your media quickly.

If either is an important factor in your circumstance I would suggest a recirculating setup and add a DYI moisture trapper to prevent water getting into your scrubber

Yeah I should’ve included that option.

I do live in a cold winter area (Idaho) yet it gets got and need AC in the summer.

I’ve seen some run the recirculating system. So maybe that’s the way to go. Any issues with keeping the scrubber and water trap 3-4’ away you think?

 

[Dkmoo]

That could depend on the size of your skimmers air pump. The longer and further away the scrubber it is to your skimmer, the more your skimmer pump would need "work" to suck in air. For this reason, I put my scrubber right next to to skimmer. If your skimmer is oversized compared to your system it may not matter much. But if you see a noticeable decrease in your foam, then maybe you'll need to either make it closer, or add a secondary air pump to help with the air movemebt.

 

[Adamantium]

Definitely go for the recirculating option with a moisture trap. I’ve been running one for a month and a half, and the media is barely half used. WAY longer than if it was just pulling in dry air.

 

[Dkmoo]

O, and actually before you invest in this set up do the simple test with aerating a cup with outside air and inside air to see if you actually do have a co2 issue.. randy detailed that simple test in many of the from posts that you can check out.

 

[Mical]

You can make one inexpensively a BRS mini reactor & this media -> https://www.shopmedvet.com/product/soda-lime-3-lb-bag/anesthesia-respiratory#minicart_a

 

[ID-Reefer]

You can make one inexpensively a BRS mini reactor & this media -> https://www.shopmedvet.com/product/soda-lime-3-lb-bag/anesthesia-respiratory#minicart_a

Is this media better than the BRS stuff?

 

[ID-Reefer]

Definitely go for the recirculating option with a moisture trap. I’ve been running one for a month and a half, and the media is barely half used. WAY longer than if it was just pulling in dry air.

I’ll run the aeration test tomorrow to hopefully confirm it’s not an aeration issue. I was looking at other setups - one like you described. Saw this one in the photo below. Recirculating and with a moisture trap/humidifier. It appears the cost of two BRS scrubber canisters is the cheapest route (except for a DYI). One for the CO2 media and one for water installed inline. Any thoughts on that?

 

[Mical]

Is this media better than the BRS stuff?

Basically same stuff but cheaper

 

[Dkmoo]

Is this media better than the BRS stuff?

IME, the airflow, water flow rate, the physical set up, and time water is exposed to bubble surface has bigger impact to the effectiveness of your scrubber than the media, which all generally perform more similarly. For me - i had struggled with why mine initially wasn't working as i thought it would, and changed a few medias to no avail, before i figured out that my intake was "too wet" that it obstructed air flow into the media, and that my skimmer air pump was too weak with the increased "air load" that it didn't produce enough bubbles that was exposed to the skimmer water long enough to allow for sufficient air exchange.

as for the moisture trapper - it's very easily DYIed if you don't want to spend money on the second canister. I just used the single BRS canister and what i did was run the tube from the skimmer collection cup lid (for the recirculating design), into a 1 pint chinese take out soup container, drill two holes on the lid. connect the other end of the air tube into 1 of the holes, then connect another airtube between the second hole and the "in" of the scrubber canister. then finally either duct-tape or silicone the tube to the container lid to make it airtight. Just place the trapper on a low place compared to your canister to make sure any condensation collecting in the airtube is tripping back down into the container.

 

[Mical]

IME - I found ZERO advantage to running intake line to skimmer (recirculation mod). I compared between both my tanks and on both trials the scrubber that was attached to the skimmer went through more media and showed lower Ph.

Recirculation of skimmer air doesn't make sense to me, I can get more air to skimmer(s) from outside (AKA room air) than I can via skimmer(s) and my tracking via Apex confirms that.

One thing I did find adding a small amount of ROX Carbon extended the media life by almost 2 weeks.

 

[ID-Reefer]

IME - I found ZERO advantage to running intake line to skimmer (recirculation mod). I compared between both my tanks and on both trials the scrubber that was attached to the skimmer went through more media and showed lower Ph.

Recirculation of skimmer air doesn't make sense to me, I can get more air to skimmer(s) from outside (AKA room air) than I can via skimmer(s) and my tracking via Apex confirms that.

One thing I did find adding a small amount of ROX Carbon extended the media life by almost 2 weeks.

 

[ID-Reefer]

@Mical So you run the skimmer intake to the scrubber and then pull air from inside your cabinet?

ROX just mixed in with CO2 media or?

 

[Mical]

@Mical So you run the skimmer intake to the scrubber and then pull air from inside your cabinet?

ROX just mixed in with CO2 media or?

Yes I pull room air to scrubber then in to skimmer. I put a small layer of rox on top of media

 

[Jorgehiram]

IMHO- Recently I had similar issues with my 125G mixed reef, PH of 7.6 at night and 7.8 max during the day, I did the aeration test and decided to try a BRS C02 reactor and recirculating did not make any difference in my case, tried pulling air from the outside and helped a little PH increase was 0.1 not stable nothing significant. After 3 weeks I decided to take another approach. Did lots of research @Randy Holmes-Farley; PH changes due to Co2, Carbonic Acid, photosynthesis, etc...
Added Kalk to my ATO in addition to the DIY 2 parts (soda ash not the Sodium Hydroxide recipe) and after one week so far very stable results PH 8.0 - 8.2 with minimum effect on Alk and CAL (2 parts).
It was easier to work on the Co2 already in the water without the Co2 scrubber .

Take a look at this from the Reef Builders and reefs;

 

[ID-Reefer]

IMHO- Recently I had similar issues with my 125G mixed reef, PH of 7.6 at night and 7.8 max during the day, I did the aeration test and decided to try a BRS C02 reactor and recirculating did not make any difference in my case, tried pulling air from the outside and helped a little PH increase was 0.1 not stable nothing significant. After 3 weeks I decided to take another approach. Did lots of research @Randy Holmes-Farley; PH changes due to Co2, Carbonic Acid, photosynthesis, etc...
Added Kalk to my ATO in addition to the DIY 2 parts (soda ash not the Sodium Hydroxide recipe) and after one week so far very stable results PH 8.0 - 8.2 with minimum effect on Alk and CAL (2 parts).
It was easier to work on the Co2 already in the water without the Co2 scrubber .

Thanks for your post. Tough call trying to decide how to deal with low PH. Ive never used limewater or a scrubber before so Im new to this. Adding Kalk to ATO seems fairly easy to do but what about it sitting in an a ATO reservoir? Does it create a sludge in the bottom? I have a 16 gal. ATO tank with an ATK pump sitting on the bottom. Am I at risk of a pump failure or other problem with this method?

A dripper or Kalk stirrer reactor I guess is another option but then that seems more complicated and then thats another needed water line if I understand correctly...

And how does all of this effect my 2 part dosing?

 

[ID-Reefer]

So I ran the aeration test. First I calibrated my apex ph probe to be sure it’s measuring accurately. Tank as is at this time before lights come on was 7.95

Aerated a cup of tank water with airstone and outside air for 30 minutes. Measured 8.15

aerated a cup of tank water with airstone with inside air for 30 minutes. Measured 7.99

then measured tank again and again got 7.95

so guessing outside air isn’t going to help much? Would a scrubber? Is kalk the answer?

because it’s a newer tank I haven’t started dosing anything yet. Have my DOS pump and two part ready to just haven’t started yet. Will bringing my alk up from 8.5 using soda ash also bring my ph up over 8?

 

[Dr. Jim]

There is a school of thought suggesting that recirculating is not an ideal way to set it up because you are losing the ability to get fresh air (oxygen) into your system. It is difficult to saturate saltwater with oxygen as compared to freshwater, so IMO, it is best to not recirculate.
Running a pipe (or tube) 10' is no problem. Mine is much longer. I use 1" PVC pipe but in retrospect I could have probably used 3/4". IMO running a line to outside air is more important (and beneficial) than the scrubber itself. The combination of the two will greatly increase your pH.
I bought 3 canisters on Amazon with 3/4" inlets. This will allow a nice size tube. The last canister has carbon. The first two have the media. (One is swapped for the other as the first one exhausts). I believe you can pull air a very long distance with 3/4" tubing or pipe.

 

[Jorgehiram]

Thanks for your post. Tough call trying to decide how to deal with low PH. Ive never used limewater or a scrubber before so Im new to this. Adding Kalk to ATO seems fairly easy to do but what about it sitting in an a ATO reservoir? Does it create a sludge in the bottom? I have a 16 gal. ATO tank with an ATK pump sitting on the bottom. Am I at risk of a pump failure or other problem with this method?

A dripper or Kalk stirrer reactor I guess is another option but then that seems more complicated and then thats another needed water line if I understand correctly...

And how does all of this effect my 2 part dosing?

It is really not bad and really easy, the bottom sludge is very thin, the pump is lifted from the bottom with a DIY spacer or cut some egg crate to lift the pump from the bottom, the pump I am using is very small and inexpensive. I removed a 10G tank/ATO and now using 5g containers with pre-made alk, for the ATO I configured with a float switch to stop the pump at a pre determined max level very low tech, or you can dose a portion of your evaporation needs with this 5g containers.