My CO2 Scrubber

[DRThompson]

Thought I would document this.

My pH currently ranges from 7.8 - 8.1. I dose 2 part and my Alk stays pretty constant at around 8-9dkh. Ca stays around 400. I use to add Kalk to my top off but found it would make my alk and pH swing too much.

I would like feedback on others who have tried this.

For those who dont know what a CO2 scrubber is:
What is a CO2 scrubber?
A CO2 scrubber is simply a small external DRY reactor which holds media that extracts excess CO2 from the ambient air.

Why use a CO2 scrubber?
The primary benefit of a CO2 scrubber is a higher pH in the tank.

How does it work?
The CO2 scrubber is simply a reactor holding media called SODA LIME (which is mainly comprised of calcium hydroxide, yep, that same pickling lime you use/see in kalkwasser - yet in a different media format). Soda Lime is commonly used in medical equipment and re-breathers for divers or firemen, and is a granular media which absorbs CO2 from air as it is drawn (or forced) through the media.

 

[DRThompson]

Bought the soda lime at shopmedvet, each bag (see picture) is 3lbs and I purchased 4 bags or 12lbs for about $30

The container is a BRS bio pellet reactor that I wasnt using. I have seen posts of people who use soda bottles, gatorade bottles...etc.

Here it is installed under my tank connected to my skimmer intake.

I would like feedback on:
Which container works best for you?
How much media do you use?
How often do you change the media?

I realize there is a color change and I've also read that if left too long the media will release the CO2 that it has stored.

 

[nivram]

What are you looking for in a higher ph?

Also which alk recipe are you using?

 

[DRThompson]

What do I expect the CO2 scrubber to do for me?
Looking for more O2 in the water, better coral growth, higher, more stable pH, healthier reef.

I buy from BRS and use their CaCl and Soda Ash (sodium Carbonate)

 

[Crackem]

I use a brs universal air filter. I fill the cannister about 3/4 full. You will notice that the media will turn purple starting at the top and working its way down. Mine usually lasts anywhere from 2-4 weeks. When most of the media is purple it's time to change it. Also when you notice your ph starting to stay at a lower amount its a good sign it needs to be replaced. The universal air filter allows air to travel from the bottom of the cannister and flow to the top. I'm not sure if your cannister is the same. Also it looks like you might have a little to much media in yours but I'm sure it will still work as long as you have air flow inside it.

 

[DRThompson]

Results so far: I installed this last night about 9pm after my lights went out. My pH increased to 8.1 and held throughout the night. (see picture)

 

[nivram]

After re-reading your first post. Im not sure why I thought your objective was to raise ph. In any event I'm glad to see you documenting this.

I know an old member Chuck ran this when it first came out using the setup Brs sells. If I remember correctly he was running it to raise his ph. But wasn't impressed with the results.

It'll be interesting to see your results. How are you going to determine increased oxygen levels? Would ORP be something worth monitoring before you start using this and comparing those values against the values obtained running your system with the scrubber I stalled?

 

[DRThompson]

After re-reading your first post. Im not sure why I thought your objective was to raise ph. In any event I'm glad to see you documenting this.

I know an old member Chuck ran this when it first came out using the setup Brs sells. If I remember correctly he was running it to raise his ph. But wasn't impressed with the results.

It'll be interesting to see your results. How are you going to determine increased oxygen levels? Would ORP be something worth monitoring before you start using this and comparing those values against the values obtained running your system with the scrubber I stalled?

Another problem I didnt mention is when my Natureef Denitrator flushes it puts abou 15gal of water with NO oxygen back in my tank. I see a pH down spike every time it flushes.

I Dont have an ORP meter .

I took the pictures this morning after running it for about 12 hours. If you look close you can already see the purple in the bottom of the reactor. I'm not sure the medial will last long.

 

[treetopflyn]

That's for this post. Been thinking about adding this to my tank to increase PH. With the family home this summer my PH has dropped .2 on avg

 

[Biggar]

Dave, thanks for this information. Very informative.

Let us know how the corals respond after a couple weeks

 

[gatoralum69]

The reason I started doing this a few months ago was that I noticed that during the winter months when we had the sliding glass doors open all the time my PH was constantly at 8.3 and at night when we closed them it would drop to about 8 or so. Now once it go hotter and it was time to close doors and kick on the AC full time, PH dropped to 7.7 an would not go above 7.9 even though I tried increasing alk to about 11 from 8. Now, ever since adding this same scrubber idea I am between 7.87 and 8.1 even though the AC is on 24x7.

 

[nivram]

Ok we need to start a get an orp probe fund for Dave. Lol I may have one somewhere in my stash. If I can find it, you can use it.

 

[gatoralum69]

I just ordered one

 

[Biggar]

Armando, now I feel like I need one. lol

Where did you get it?

Im still looking for good sale on the EB8. 10% is the best i can find, where did you get yours so cheap?

 

[DRThompson]

Well, it's been 36 hours since I've started the CO2 scrubber.

Pros:
Since I started the scrubber, the pH has been between 8.1 and 8.25 (see chart below). Since less CO2 is entering my system, I have to assume my O2 levels are up!

Cons:
almost all the media has turned purple (see pic below). I'm going to leave it in until my pH drops. I was hoping it would last a couple of weeks at least

 

[billsreef]

Dave,

O2 in seawater does go up from a reduction in CO2, they are completely independent

 

[shaggss]

I've added one too as my pH was 7.65 at times. Tried EVERYTHING else. This has worked great for me and my pH now is 7.9-8.1. I was using a single brs reactor but my media only lasted 8-10 days. So I have added another rector. Lets see how long it lasts for now.....

 

[treetopflyn]

Thanks Dr. Please keep updating.

On a side not has anyone ever noticed a difference in PH when running a fan across a sump surface? I am thinking about shutting mine down since the only thing I see it doing is causing more evaporation causing me to refill my ATO more frequently. My tank runs at 77 with or without the fan.

 

[Crackem]

36 hours is unusually fast. If I were you I would either make a jug yourself or get the universal air filter. I'm not sure if your cannister works the way it should.

 

[gatoralum69]

Armando, now I feel like I need one. lol

Where did you get it?

Im still looking for good sale on the EB8. 10% is the best i can find, where did you get yours so cheap?

My EB8 was sold to me as a DC8 lol