CO2 scrubber review

[USMA36]

How do you prevent water in the skimmer should it fill up being drawn into the scrubber?

Skimmer cup, black silicone airline tubing x 2, then reactor.



We find that adding water to the reactor does not last that long. These are the instructions from brs, click on more and "directions"
http://www.bulkreefsupply.com/brs-universal-co2-scrubber.html
or
What I did above. Media lasts longer with above.

 

[drawman]

How do you prevent water in the skimmer should it fill up being drawn into the scrubber?

Probably would help to have a drain on the skimmer cup

 

[ReeferNoob77]

To prevent water from getting into your scrubber you could add another Y at the lowest point in your drip loop and feed that back into the sump, air goes up water goes down.

 

[BlueCursor]

The more I think about having air bubble through water to humidify the lye, the less I like the idea. Lye will absorb water and hold onto it. Once it absorbs moisture, it does not give it up. So that original 1 tbs of water at the bottom of the chamber may disappear, but it is held tight in the lye.

By adding more and more moisture, you decrease the effectiveness of the lye to absorb CO2. This would explain why the lye lasts longer if you bubble the air through water. The lye may last longer, but you are actually absorbing less CO2 because you have decreased its effectiveness with too much moisture. You would get more bang for your buck with less moisture (stick to 1 or 2 tbs at the start), and smaller amounts of lye so you don't absorb as much CO2 as it passes through.

 

[SuperDragon]

I've never made price comparisons, but food grade would be good enough for a reef scrubber. You don't need medical grade for a reef. The only problem is that food grade is not color enhanced, and it usually comes in powder or micro-beads. Not sure micro-beads would work.

Anything less than food grade could have some other compounds in the NaOH so it could cause issues. I wouldn't use those.

Sodasorb has KOH I found, that's likely why it's more efficient, but even a little water will mess with it and push the reaction backwards limiting use. Medical grade sounds more like pure NaOH.

"CHEMICAL ACTION SODASORB® has a 3 way chemical reaction with carbon dioxide which results in longer life and greater efficiency per weight used.The carbon dioxide first reacts with the moisture in SODASORB® to form carbonic acid [CO2+H2O = H2CO3]. The carbonic acid then reacts with the sodium and potassium hydroxides in SODASORB® to form sodium and potassium carbonate and regenerate water [2H2CO3+NaOH+2KOH = Na2CO3+K2CO3+4H2O].The caustic alkalis draw the acid gas out of the passing mixture and hold it. The sodium and potassium carbonates then react with the hydrated lime, forming calcium carbonate and regenerating sodium hydroxide and potassium hydroxide [Na2CO3+K2CO3+2CA(OH)2 = 2CACO3+2NaOH+2KOH]."

 

[SuperDragon]

How do you prevent water in the skimmer should it fill up being drawn into the scrubber?

I usually empty my skimmer every ~2 months or when I can't stand the smell . The cup in the picture is 1 gallon, it will be awhile.

Probably would help to have a drain on the skimmer cup

Or add the drain line to the cup like Drawman mentioned.

 

[SuperDragon]

Update:


So far results look more stable with scrubber attached to skimmer lid, recirculating air. If the air seems too moist, I could remove one of the airline tubes from the cup, but things look good so I'll continue. Still waiting for the "Y" then I'll likely setup parameters from 8.2 to 8.3. The guys at BRS suggested 8.2-8.25. Their reasoning is the benefit of going to 8.3 is not much different than 8.25. Anybody have ideas?

 

[EJReef]

The more I think about having air bubble through water to humidify the lye, the less I like the idea. Lye will absorb water and hold onto it. Once it absorbs moisture, it does not give it up. So that original 1 tbs of water at the bottom of the chamber may disappear, but it is held tight in the lye.

By adding more and more moisture, you decrease the effectiveness of the lye to absorb CO2. This would explain why the lye lasts longer if you bubble the air through water. The lye may last longer, but you are actually absorbing less CO2 because you have decreased its effectiveness with too much moisture. You would get more bang for your buck with less moisture (stick to 1 or 2 tbs at the start), and smaller amounts of lye so you don't absorb as much CO2 as it passes through.

It's not lye. It's mainly calcium hydroxide.

If the PH is stable, the effectiveness of absorbing CO2 isn't changing from moisture.

 

[EJReef]

Update:


So far results look more stable with scrubber attached to skimmer lid, recirculating air. If the air seems too moist, I could remove one of the airline tubes from the cup, but things look good so I'll continue. Still waiting for the "Y" then I'll likely setup parameters from 8.2 to 8.3. The guys at BRS suggested 8.2-8.25. Their reasoning is the benefit of going to 8.3 is not much different than 8.25. Anybody have ideas?

I got the Y adapter and have the air inputs from my skimmer cup and the scrubber. Not using a solenoid. There is definitely less air flow through the scrubber judging by the reduced suction on my finger.

My PH has yet to change and is still at 8.5 at the end of the lighting cycle. It is 8.35 in the morning. I haven't had any noticeable precipitation on pumps/heaters.

 

[EJReef]

 

[SuperDragon]

Wow, 8.5. What would you consider too high for pH?

 

[EJReef]

Wow, 8.5. What would you consider too high for pH?

I've read up to 8.5 is in the acceptable range. At the end of today's intense lighting period it was 8.52. I was hoping it would drop a little by adding the Y but it hasn't yet.

I'm also using kalkwasser though, so that's why it's getting so high. My alkalinity is ~8.5 dKH

 

[SuperDragon]

I've read up to 8.5 is in the acceptable range. At the end of today's intense lighting period it was 8.52. I was hoping it would drop a little by adding the Y but it hasn't yet.
I'm also using kalkwasser though, so that's why it's getting so high. My alkalinity is ~8.5 dKH

I use soda ash from brs. Do you need a scrubber if your levels are mid to high?
I added another "T" so all my air is from the skimmer cup now to so scrubber & bypass. I have to keep monitoring for a few days. Consumption of Alk is high dipping to 7 from 8 over the past 3 days, growth on my corals is noticeable.

 

[EJReef]

I use soda ash from brs. Do you need a scrubber if your levels are mid to high?
I added another "T" so all my air is from the skimmer cup now to so scrubber & bypass. I have to keep monitoring for a few days. Consumption of Alk is high dipping to 7 from 8 over the past 3 days, growth on my corals is noticeable.

My PH was 7.8 - 8.1 with the kalk before the scrubber and my corals were growing slow.

Let me know if your PH drops. You could also try one input from skimmer cup and one from scrubber to try to even out the flow.

I've been using 0.4 more dKH per day than before scrubber.

 

[SuperDragon]

Update:

My CO2 scrubber is more controllable and pH is stable at 8.2 to 8.3. No more wide swings in pH with the use of a Solenoid. Sorb lasts MUCH longer than before. Highly recommended for stability. Alk is unstable some days, but I'm slowing increasing 2 part, no rush. I'm already past double the amount of 2 part prior to addition of the scrubber. Growth is very noticeable.

 

[CoralNerd]

What's your apex code look like?

 

[SuperDragon]

What's your apex code look like?

Fallback OFF
If pH > 8.30 Then ON
If pH < 8.25 Then OFF

My code is nothing special. I went with the recommendations from BRS to see what happens.
My media is getting close to depletion and still observing when to change it. The color change is much darker with both inputs from the skimmer in recirculating config. I'm thinking if the pH goes below 8.2 I will look at it and consider changing it. Maybe this weekend.

 

[CoralNerd]

If you dose bacteria or reefbrite's reef bugs, it might mess up that ideal 8.2 to 8.3 ph. I dose the reefbugs every other night along with phytoplankton to keep my pod population healthy.
I wish I had another plug available to put in a Solenoid.

 

[drawman]

Update:

My CO2 scrubber is more controllable and pH is stable at 8.2 to 8.3. No more wide swings in pH with the use of a Solenoid. Sorb lasts MUCH longer than before. Highly recommended for stability. Alk is unstable some days, but I'm slowing increasing 2 part, no rush. I'm already past double the amount of 2 part prior to addition of the scrubber. Growth is very noticeable.

I can't say I've ever used a solenoid does it hook up to a breakout box? I would love to see updated pics of the setup!

Keep us posted on how long the media lasts too.

 

[EJReef]

I can't say I've ever used a solenoid does it hook up to a breakout box? I would love to see updated pics of the setup!

Keep us posted on how long the media lasts too.

AC power socket