CO2 Scrubber

[dirtycontour]

I've been battling low pH in my tank forever. I do not like the idea of dosing buffers or using any other chemical to raise pH. I came across a thread in another forum and decided to give it a shot. This is a typical week of my pH before I installed the scrubber.

Notice the 24th to the 26th. This is when my house is closed up.

Downbeach linked me to a place to order my soda lime. Thanks again.
http://www.wayfair.com/Molecular-Products-Gallon-Pail-Sodalime-120020-00-AMW1000.html

Shipping was free and fast. Sooo, I got a gatorade bottle and drilled a bunch of small holes in the bottom to let air inside.

I drilled a hole in the cap to insert some tubing I had laying around.

Connected the extra tubing to the skimmer's air silencer.

Here she is, up and running.

Now, it's only been one night but I have seen definite improvement. I do not mind a 0.3 swing but I would like to stay within an acceptable range. I topped out at 8.29. The only thing left to see is how long the soda lime will last me.

 

[Mark...]

Interesting tool. You would think the bubbles in the skimmer would release enough CO2 so as not to not be an issue.

 

[downbeach]

Interesting tool. You would think the bubbles in the skimmer would release enough CO2 so as not to not be an issue.

CO2 is in the atmosphere too. So, if you have elevated levels of CO2 in your household atmosphere, through gas exchange, your pH in your system, will go down. If you can open windows, the CO2 levels will go down, and your pH will go up. By removing the CO2 via a scrubber, you are introducing less into your system, and keeping your pH up.

 

[Mark...]

CO2 is in the atmosphere too. So, if you have elevated levels of CO2 in your household atmosphere, through gas exchange, your pH in your system, will go down. If you can open windows, the CO2 levels will go down, and your pH will go up. By removing the CO2 via a scrubber, you are introducing less into your system, and keeping your pH up.

I wonder how many plants it would take to make a difference.

 

[Zippy69]

Not many, but once the lights go out they suck up oxygen too.

 

[mrehfeld]

Thanks for sharing I look forward to future updates about how it's working for you.

 

[redfishbluefish]

Anything in the 8's or even 7.9 or so an above is good with me. Could you have accomplished the same thing by running your skimmer air supply through a tube out the window (pulling is fresh air)? I've got to believe you are going to be going through soda lime pretty quickly. This is the same stuff they use in re-breather scuba equipment. It's costly, but I believe can be regenerated. Thanks for sharing.

 

[Zippy69]

Anything in the 8's or even 7.9 or so an above is good with me. Could you have accomplished the same thing by running your skimmer air supply through a tube out the window (pulling is fresh air)? I've got to believe you are going to be going through soda lime pretty quickly. This is the same stuff they use in re-breather scuba equipment. It's costly, but I believe can be regenerated. Thanks for sharing.

Used in anesthetic machines to.

 

[dirtycontour]

Anything in the 8's or even 7.9 or so an above is good with me. Could you have accomplished the same thing by running your skimmer air supply through a tube out the window (pulling is fresh air)? I've got to believe you are going to be going through soda lime pretty quickly. This is the same stuff they use in re-breather scuba equipment. It's costly, but I believe can be regenerated. Thanks for sharing.

Ideally, I would have loved to run the airline outside, but it is not an option in my apartment. I'm hoping I don't run through the soda lime too fast. I read a bunch of reviews and it was 50/50. Some people claim the bucket I bought lasts well over a year, others run through it quickly...I've got my fingers crossed.

I will try to find if there is a way to regenerate it.

 

[Hockeynut]

Very interesting thanks, I read a thread about this on RC but had very mixed reviews. Ill be watching to see your results long term

 

[dirtycontour]

One week of CO2 scrubbing

I installed the scrubber last Saturday, so it's been going for a week. My pH has improved. Lows of 7.9ish to highs of almost 8.3. Problem is that last night I noticed some of pellets had turned purple. The color change indicates that the media is exhausted(it's a temporary color change). The plan is to leave the media in the reactor and monitor pH closely the next few days. When it starts slipping to uncomfortable levels, I'll make a bigger reactor so media changes are less frequent. Here is my graph of the past week.

 

[Zippy69]

Just for curiosities sake, how would one recharge the media? If you were to flood it with pure o2 or some alk based gas would it reconvert?

 

[dirtycontour]

Just for curiosities sake, how would one recharge the media? If you were to flood it with pure o2 or some alk based gas would it reconvert?

From the minimal research I did, I do not think there is a way to recharge it...
If anyone knows a way, I'm all ears.

I should have mentioned that while I was looking at the bucket today, I noticed an expiry date of Sept 2013. I'm not sure if that means anything? I emailed wayfair, I'll post their response when I get it.

 

[downbeach]

I made one a few weeks ago out of an old RO chamber I had laying around. I received the soda lime on Monday, and installed the unit on Tuesday, so I'm on my 5th day. I have seen an improvement of about .3 in my pH(using a pinpoint meter with a lab grade probe). I wasn't sure how much soda lime to put in the cartridge, so I only filled it about 3/4 full, for fear of inhibiting air flow to the skimmer. About half of the soda lime has turned purple. And, until yesterday, my windows have been open all day. I bought the media in 3 lb bags, so I should get a good idea what this will cost. Since the air intake is located in the cabinet, I have added an additional piece of 1/2" tubing so the air would be taken from outside the cabinet, so we'll see.

 

[dirtycontour]

I hadn't thought about sucking air from outside of the cabinet. I'll give that a shot as well.

 

[downbeach]

As of tonight, the soda lime has completely turned purple, so tomorrow, I'll recharge and monitor.

 

[dirtycontour]

Wayfair sent me another bucket of soda lime, since the initial bucket was expired. I haven't opened the new since the old seems fine. I'm running through a small Gatorade bottle every seven days so far. How long will the bucket last? I don't know yet, I'll have to do some maths...

 

[downbeach]

It appears I'm getting about a week out of a full cartridge. According to the BRS web site, you're supposed to get 7 refills out of 9 lbs. of the media. Using these numbers, I should get about 29 refills out of a bucket of the media from Wayfair. The cost works out to around $4.00 per week, in my system. One caveat here, during this trial period, my windows have been open, so I don't think I'll be getting a full week, once the weather gets to a point that I'll have to keep the windows closed.

 

[Hockeynut]

Do you guys see and positive affect in your tanks so far?

 

[dirtycontour]

My windows have been closed for the past week or so. I have not noticed any change in the life of the media. I'm assuming the media does not have to "work" when the windows are open?

Some rough math tells me a bucket will last me about 43 weeks. I'll estimate that costs me $100/year.

Rob, I wish I could tell you that my corals are growing out of the tank since installing the scrubber, but it may take more time to tell if it is really worth it. If anything, it gives me some peace of mind to check my pH graph and see it consistently in the acceptable range