DIY CO2 Scubber for BioCube 29 Skimmer

[Water Dog]

So... I have been having low PH issues with my BioCube 29. The PH, even with the windows open was hovering around 7.6 at night and 7.8 during the day. I decided to make a DIY CO2 scrubber for my Aquaticlife 115 Skimmer with an already installed airline mod. I don't see why this wouldn't work for any skimmer with an airline tube extension.

 

I purchased an inline water trap from EBay, 2 for $10.00 plus free shipping.

 

Make sure you get the Salter Labs 7001 water traps, as they have unscrewable end caps.

 

Then I cut off the inner tubes so I could fit as much media as I could inside of the cylinder.

 

I went to a local dive shop and bought a bag of color changing soda lime, it's a CO2 absorbent material used for scuba rebreathers or for ventilators in the medical field. I believe you can get it at BRS also for $50 for a 9# jug.

 

Here are the finished products, my mini DIY CO2 scrubbers. Here are the two scrubbers that I made that I will rotate as they get exhausted. Note the purple color change beginning in the top one. On the right end, you can see a purple discoloration. It has been in use for about 3 days now, so I guesstimate each cylinder will last a little over a week before it needs to be swapped out.

 

Here it is attached to the airline on my Aquaticlife 115 skimmer.

 

So far so good. Whereas my PH before hovered between 7.6 to 7.8, even with the windows open, it now hovers between 7.9 and 8.1. It also makes for one helluva silencer for your noisy skimmer air intakes. I hope you found this helpful!

[Fnard]

Well played. Turned out really nice. Been thinking of doing something along these lines too since my pH is always low. Don't look like those will be big enough for my tank, 65 gal, but will take a look to see if I can find something similar in a larger size.

[ManGups]

Sweet .. I made one using a TLF 150 phosban reactor and attached it to the input of the Tunze 9004 air intake. I used the TLF co2 absotbant media. The ph runs around 8.15-8.2 during the day and around 7.9 at night.

 

The TLF media is supposed to change color too but I have no change in color at all in a month. However the Ph did over up the scale for day and night by 0.2

[Water Dog]

Well played. Turned out really nice. Been thinking of doing something along these lines too since my pH is always low. Don't look like those will be big enough for my tank, 65 gal, but will take a look to see if I can find something similar in a larger size.

BRS sells a universal air filter made out of an RO filter housing that you could use. It's pretty cheap too at $30. Depending on the size of your skimmer airline though, you may have to swap out their elbow fittings to a 1/4" npt x 3/8" barbed elbow which they also sell.

[Fnard]

BRS sells a universal air filter made out of an RO filter housing that you could use. It's pretty cheap too at $30. Depending on the size of your skimmer airline though, you may have to swap out their elbow fittings to a 1/4" npt x 3/8" barbed elbow which they also sell.

Thanks for the heads up. May have eventually found that, but less work for me now. I love it when that happens. Funny thing is, I was looking to see if I could retro my spare brs reactor to do this. Def easier this way.

[ManGups]

Here is what it looks like:

[Water Dog]

Very nice! One of the things I love most about this hobby is McGuyvering things together to fit random applications for our reefs.

[MrJoel]

I may need to set one of these up if my tank does not settle down after cycling is complete. Looks like a nice solution for a tiny tank compared to the giant canisters that are usually sold for co2 scrubbing. 

[MrJoel]

Made one of these yesterday. The media is already changing color and my PH is up from 7.6 to 8.2. We'll see how often I have to swap out the soda lime.

This is great. Thanks Water Dog.

[Han Solo]

I'm going to make one of these because I have low PH as well.

 

However I don't have a skimmer on my 40B, just a canister filter and a GFO reactor. So only surface agitation for air exchange. I have seahorses so I don't want to add an airstone since it's not good for them. Anyone have suggestions on what I could do?

[MrJoel]

Well they only help in removing CO2 from the air being added into the water column. With no Skimmer that will not really help you. You may want to check Alkalinity and It could be contributing to your PH.  Also if you are not already doing so, regular phytoplankton dosing is said to assist in stabilizing PH and it certainly would not hurt in a tank with sea horses.

[Han Solo]

My alkalinity is low. I'm taking steps to fix that with a two part solution and I also sometimes dose phytoplankton, but I will try and do that more often. My KH is like 6 and my ph is around 7.8. Is that too low? I have lows of gorgonians and soft corals. No SPS. 

 

Right now I have a canister filter with just foam and chemipure, and the GFO reactor. I am think about replacing the canister filter with a HOB protein skimmer. What do you think about that idea? Or keep the canister running as well? Would allow me to use this scrubber as well. 

[RayWhisperer]

Ph will fluctuate all the time. Don't bother trying ti keep it up. Your alk is way low, 6 dkh is borderline deadly for many corals. My guess is you are dosing 2 part incorrectly. Best way to fix that is to do a large volume water change. This will bring the water back close to NSW. Then start testing first, then dose accordingly.

[Han Solo]

3 hours ago, RayWhisperer said:

Ph will fluctuate all the time. Don't bother trying ti keep it up. Your alk is way low, 6 dkh is borderline deadly for many corals. My guess is you are dosing 2 part incorrectly. Best way to fix that is to do a large volume water change. This will bring the water back close to NSW. Then start testing first, then dose accordingly.

I actually haven't been dosing 2 part yet. I am going to start though. Would this be good? https://www.amazon.com/gp/product/B000O37D7Q/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1

[RayWhisperer]

That'll work fine. Do a large water change to get parameters back close to NSW. Test, then test again the same time the next day. If there isn't much of a change, test every day until you get a drop. That'll give you a baseline of how much you'll need to dose, and how often.

[Han Solo]

9 hours ago, RayWhisperer said:

That'll work fine. Do a large water change to get parameters back close to NSW. Test, then test again the same time the next day. If there isn't much of a change, test every day until you get a drop. That'll give you a baseline of how much you'll need to dose, and how often.

Thanks for the advice. It comes on Tuesday along with a bucket of Red Sea salt. The whole lifetime of the tank I've used Instant Ocean reef crystals, and I wanted to try Red Sea as I've heard better things. 

 

Would you recommend over a 50% water change before the  testing?

[RayWhisperer]

As much as it takes to bring parameters back to NSW levels. With alkalinity that low, I wouldn't be worried about a change in salt, or a rapid change in levels. Stability is the goal, but when something is way out of whack, it's better to fix it fast.

[shiftline]

Nice DIY!   Thats a decent jump in PH!  how long does that little holder last before you have to change it?

[Water Dog]

I bought two of those inline water trap things...  I rotated them out every week and a half to two weeks.

[alphapapa]

Just bought some of these traps and the media. I've been using kalk to keep the ph up but my icp test showed high levels of co2. I've tried open windows, plants near the tank, macro algae, air stones, removing tank lid, more circulation and surface agitation. Added a skimmer, but no increase and no air intake tubing. So I hope this works using my air stones. 

 

Appreciate the share

[mcarroll]

On 8/23/2023 at 9:54 PM, alphapapa said:

Just bought some of these traps and the media. I've been using kalk to keep the ph up but my icp test showed high levels of co2. I've tried open windows, plants near the tank, macro algae, air stones, removing tank lid, more circulation and surface agitation. Added a skimmer, but no increase and no air intake tubing. So I hope this works using my air stones. 

 

Appreciate the share

I didn't think ICP would be very accurate for pH (which is a combo of alk and co2) due to the time and extra handling between the sample you take and the result you're getting.  (Do they even measure pH with ICP?  I think it may be measured separately.)  Most folks don't use ICP tests for measuring things like pH (or CO2).

 

What pH level did they measure?   What pH do you measure with your own test kit?  And what is the system's alkalinity?

 

In any event, CO2 is a coral fertilizer....fuel for photosynthesis.  Chances are, even if CO2 is "high", it's not a problem for the tank.

 

But...

 

If CO2 really is at a high concentration in your house, it can be a real health hazard for YOU.  (If the CO2 concentration in your house ISN'T high, then the level is not going to be high in your tank either.)

[nanoreeFan]

Anyone think can you also put this on the the intake of an airpump/airstone ? Will it harm the corals? I tried it as an experiment and all the corals closed right up.