CO2 Scrubber...

[diablomaster9045]

Hello Randy,

I was wondering what your thoughts are on using a container of soda lime on the air intake of a protein skimmer to increase ph without affecting alk?

IE a C02 scrubber


Thanks!

 

[redfishbluefish]

My two cents.....CO2 scrubbers get very expensive real fast. Have you checked the price and the frequency you'll need to change. Before I ran a CO2 scrubber, I first try running my skimmer hose outside. Oh, and I'm assuming you have low pH.

 

[cdness]

I ran one, but I exhausted the media in less than 2 full days... It would have been too expensive to run long term. There is a way to regenerate the media, but it never hits 100% effectiveness again.

 

[Randy Holmes-Farley Verified Community Expert]

The effectiveness depends on how much aeration the tank gets through other means, such as the tank top.

They can help boost pH, but as noted, can get expensive.

I discuss them briefly in an upcoming article.

 

[Downbeach]

The soda lime can get expensive, so I used to run my CO2 scrubber only when I had to close up the house, i.e. running the AC or heater. It wasn't practicable for me to run a hose to an outside air source, since my system was located in the center of the foyer. But, that would have been a better, less expensive choice. I found it more economical to buy it in 5 gal. buckets from Medvet.

 

[diablomaster9045]

My two cents.....CO2 scrubbers get very expensive real fast. Have you checked the price and the frequency you'll need to change. Before I ran a CO2 scrubber, I first try running my skimmer hose outside. Oh, and I'm assuming you have low pH.

Its low ish. 7.9-8.1 before I started using a C02 scrubber. I have not checked the PH since. I have been using the BRS color changing soda lime for the past 6 months and have yet to see it change color from the white it is.

 

[beaslbob]

before doing any of these things I would:

1) measure pH just before lights out.

2) add/increase macro algaes in a refugium.

IMHO macros will increase pH much faster, cheaper, and more effectively than co2 scrubbers, outside air and so on.

my .02

 

[DGee]

In our previous house I struggled with low PH and building a co2 scrubber took my tank form 7.3-7.5 to 8.1-8.3

Don't waste your money on the BRS soda lime, MedVet International has what I found to be longer lasting for much cheaper.

MedVet has 3lb bags for $7.80 where BRS is selling you 5lb for $50.

http://www.shopmedvet.com/product/soda-lime-3-lb-bag/jorgensen-products-anesthesia-products

In my old tank, which had about 110 gallons of water volume a 3lb bag would last me about 4 months on my small scrubber.

 

[DGee]

I should also add I think they still have free shipping over $50 and MetVet has all kinds of good stuff you can use on your tank too, bone snippers for fragging and all kinds of other goodies we use on our tanks for really good prices.

 

[neuwave]

When you buy a bucket of soda lime it will go a long way. I've seen a 5 gallon bucket of soda lime as low as $65 and high as $80. My buckets last a bit over a year. Changing two RO canisters every 2-3 weeks. So even at the one year mark that's less than $7 a month.

 

[diablomaster9045]

before doing any of these things I would:

1) measure pH just before lights out.

2) add/increase macro algaes in a refugium.

IMHO macros will increase pH much faster, cheaper, and more effectively than co2 scrubbers, outside air and so on.

my .02

I have probably a 10g refugium chamber in my sump and it is packed with macroalgae. I have it on alternating light schedules. It helped the major dips in the night.

 

[jedimasterben]

Its low ish. 7.9-8.1 before I started using a C02 scrubber. I have not checked the PH since. I have been using the BRS color changing soda lime for the past 6 months and have yet to see it change color from the white it is.

That's because the media changes from white to a light purple and then back to white after a short time.

 

[shornik]

I'm thinking of going the c02 scrubber route. So the way I understand this I would attach an air tube from my skimmer to where the Soda Lime is stored. My question is where do you put the soda lime, in the tank/sump, or outside? If outside do you just put it in some kind of jar or something? Also, I read on an old discussion forum someone who also used Carbon in their scrubber, does that make sense too?

 

[Randy Holmes-Farley Verified Community Expert]

You pump air through some sort of container that contains the soda lime, and then to your skimmer inlet. High contact area between the soda lime and the air is important, so don't just pass the air over the top of a pile of solids.

 

[shornik]

So like a regular fish tank pump, hooked up to the container pumping air through, and then a line from that container to the skimmer? Sounds like it might get noisy? I was thinking of just sticking the line from the skimmer to outside of my house using a hole that the cable comes in from. would that be better/easier? Should I worry about pollutants from the outside coming into my tank? BTW, my PH is pretty consistently been around 7.7 - I don't think its ever been 8.0 or higher even with dosing Kalk water.

 

[Downbeach]

I made one out of an old RO unit canister, using the DI resin insert.

 

[Downbeach]

If you can just run a line to an outside air source, I'd try that before a CO2 scrubber. Just run a 1/2" line from the input of your skimmer to the outside air source, your skimmers air intake will be all you need.

PS I did make the same unit for someone who wanted to filter the air going into their skimmer from the outside, just used a proper carbon instead of soda lime.

 

[Randy Holmes-Farley Verified Community Expert]

Outside air will also be a lot cheaper, if it works well enough.

 

[shornik]

Thanks everyone, especially for the visuals I needed that. I'll post back here once I get this running, first I'll try just a line to the outside and see how that goes....

 

[Randy Holmes-Farley Verified Community Expert]

Thanks everyone, especially for the visuals I needed that. I'll post back here once I get this running, first I'll try just a line to the outside and see how that goes....

Make sure it isn't restricting air flow to the skimmer much.