Has Anyone Tried Liquid CO2 for "High Maintenance" Plants?

JustAFishServant

Well Known
Member
Messages
1,618
Hey all! I was doing aquarium research as usual, and started thinking about "liquid co2"; seachem excel, aqueon leafy green and api co2 booster. I started wondering if people who inject co2 have experimented using liquid supplements for "high maintenance" plants; dwarf hairgrass and dwarf baby tears, for example. How was the yield? Did the plants thrive, or was injection superior, as I'd suspect?

Note: I don't plan on growing "high maintenance plants" nor do I wish to try co2 injection. I'm just curious: has anyone tried replacing injection for baby tears or hairgrass with liquid co2 instead?

Most use liquid co2 for algae eradication; it must have a positive effect on plants if they thrive, and algae dies...is it "good enough" for picky plants?

As always, I thank you all for stopping by. Be kind and respectful to all who contribute. Thanks all :)
 

Advertisement
Injection is superior and much, much cheaper than liquids if the latter is intended as a carbon source, given the fact that plants must extract the carbon from the organic contents of 'liquid co2'. And the amount is at best very limited and the exact mechanism is unclear.

Besides organic contents, there might also be true CO2 in liquid CO2. Similar to regular water :D.

If you want to use it as a carbon source, given the extreme inefficiency, I would recommend it for 'low energy conditions' (low light intensity) only, but certainly not 'picky plants'. But even then....

Plants considered 'picky' are those that struggle in fully submersed conditions due to lack of sufficient CO2.

Hairgrass is not on my list of picky. Dwarf baby tears is on the list.
 

Advertisement
These "liquid CO2" products are a dilute solution of gluteraldehyde. In higher concentrations, this chemical is use as as a high-level disinfectant in hospitals to kill bacteria, fungi, and viruses. Thus, while sold as a "carbon precursor" its best use is to kill algae, especially the dreaded black beard algae. See the video below from the Danish plant experts at Tropica.


If the product kills algae in your tank, it will not be competing with your plants for the available CO2.

Some fish keepers have used vodka as a source of carbon in their planted tanks. If you are of responsible drinking age, this might be an option. However, the vodka is for the tank, not drinking. To convert vodka to CO2, you need a CO2 reactor with reduced oxygen content. In a marine aquarium, this anaerobic process can take place within the reef or live rock. If you pour too much alcohol into your freshwater tank, it will kill the fish. The same thing applies to gluteraldehyde. To much is fatal to your fish and if you are not careful, you could also be poisoned.
 
I’ve used the api co2 booster. It is expensive and needs to be used daily. It’s really just an algeacide.
 
  • Thread Starter
  • #5
These "liquid CO2" products are a dilute solution of gluteraldehyde. In higher concentrations, this chemical is use as as a high-level disinfectant in hospitals to kill bacteria, fungi, and viruses. Thus, while sold as a "carbon precursor" its best use is to kill algae, especially the dreaded black beard algae. See the video below from the Danish plant experts at Tropica.


If the product kills algae in your tank, it will not be competing with your plants for the available CO2.

Some fish keepers have used vodka as a source of carbon in their planted tanks. If you are of responsible drinking age, this might be an option. However, the vodka is for the tank, not drinking. To convert vodka to CO2, you need a CO2 reactor with reduced oxygen content. In a marine aquarium, this anaerobic process can take place within the reef or live rock. If you pour too much alcohol into your freshwater tank, it will kill the fish. The same thing applies to gluteraldehyde. To much is fatal to your fish and if you are not careful, you could also be poisoned.
Oh yes, I should've mentioned: I know that these supplements are gluteraldehyde, that it's used in hospitals as a disinfectant, that it's toxic in high amounts, and that it's often used as algaecide.

The one thing I never knew is that folks use vodka. I'd never heard of this method before! How exactly does it convert into co2? Can you use the "cheap stuff"? Does it have adverse effects to fish in high amounts? I imagine it does, just like co2 injection, with the exception of it being ethyl alcohol.

Vodka is also a cleaner; great for shining windows, mirrors, and wood floors. It's often used in cologne and perfumes as well. Similar to gluteraldehyde.

Fascinating!
 
I think you are actually better served by drinking it (provided....age....) and then looking at your tank and think it is the most lush plantjed tenk in se universche....

Plants can only utilise CO2. Externally or internally (within the plant), certain compounds containing C, are able to convert to CO2.

But these compounds might have averse effects also. Ethanol (vodka) doesn't sound beneficial to microbiota.
 

Advertisement
I think you are actually better served by drinking it (provided....age....) and then looking at your tank and think it is the most lush plantjed tenk in se universche....

Plants can only utilise CO2. Externally or internally (within the plant), certain compounds containing C, might convert to CO2.

But these compounds might have averse effects also. Ethanol (vodka) doesn't sound beneficial to microbiota.
Oh so true man! Just a couple of shots and my tanks look great!! :). No need to change watter! Darn! I wonder how good they’ll look with tequila:). Luv ya man!!!
 
I have tried using Excel as a "CO2 booster" in low light tanks with plants that are perfectly happy without CO2 injection. It does seem to help a little. CO2 injection makes so much more of a difference though. They aren't really comparable.

I haven't tried using Excel to grow "high maintenance plants," but I can't image it would do enough.
 
I can't answer your question but am also interested in the answer.

I use liquid CO2 and find it has a dramatic and positive effect giving lush growth with my favourite easy plants which struggle without it. I have been experimenting since 2008 so I think I have enough experience in my own situation to assert this.

I have read that liquid CO2 only kills algae and microbes on the plant leaves but the effect is much more dramatic than that.

Some authorities writers also assert that liquid CO2 gives significantly improved plant growth that is not fully explained but that CO2 gas gives even better results.

I was happily going to invest in CO2 gas but for what I want at the moment there is no need to as I am getting the plant growth I want. I would have to make an investment in equipment which needs time to set up and keep running accurately.

All I do at the moment is add a capful of liquid CO2 daily so it is very easy and reliable. For most people the cost of liquid CO2 may be an issue but not for me.

I would be interested in how far liquid CO2 can be taken in terms of which plants can be grown with it. Some people will have this knowledge.
 
I can't answer your question but am also interested in the answer.

I use liquid CO2 and find it has a dramatic and positive effect giving lush growth with my favourite easy plants which struggle without it. I have been experimenting since 2008 so I think I have enough experience in my own situation to assert this.

I have read that liquid CO2 only kills algae and microbes on the plant leaves but the effect is much more dramatic than that.

Some authorities writers also assert that liquid CO2 gives significantly improved plant growth that is not fully explained but that CO2 gas gives even better results.

I was happily going to invest in CO2 gas but for what I want at the moment there is no need to as I am getting the plant growth I want. I would have to make an investment in equipment which needs time to set up and keep running accurately.

All I do at the moment is add a capful of liquid CO2 daily so it is very easy and reliable. For most people the cost of liquid CO2 may be an issue but not for me.

I would be interested in how far liquid CO2 can be taken in terms of which plants can be grown with it. Some people will have this knowledge.
To my knowledge, only Tom Barr knows a bit more about it. The hypothesis is that the liquid is taken in and converted to either CO2 or a carbohydrate intermediary. But in any case, given the limited amount you are supposed to dose, it is nowhere near the amount of gas produced via CO2 injection. So for high energy tanks (high light intensity), liquid CO2 will fall short big time.
 
What Tom Barr said about glutaraldehyde:

GA cross links proteins. So some of it does that. Plants seem able to address this easily, most green algae also, but not the BBa so much or other species of algae.

A % of the GA dosed will get bound up. Like NH4 filter bacteria, there are bacteria that will attack the GA at low levels. Does all of this go to the plants? No, not possible.
How much goes to the plants and not other sources in the ultimate fate?

Well, I do not think as aquarist, we can answer this.
As a research question, this is a rather straight forward process.
Use stable isotope C13 labeled GA. Not cheap, but the method is well known and accepted.
This would give you a % of the GA dosed that will be on the algae, plants, bacteria, detritus etc and then the water/loss to the air above.

I think we get about 2 ppm of CO2 out of each stand dosing of 2 ppm of GA roughly. Not that much.
But we do get a lot more growth vs the non CO2 method alone also and are able to grow other species together we cannot with non CO2 methods.
So something does not really add up.

But what this might be, I'm not sure, speculation only. Algicidal properties are one part, but there's more carbon being added to the plants than what we would predict from GA alone.
When we add good CO2 gas ppm's, and add GA, we do not observe increased growth. So a carbon source from GA seems to be the only real benefit along with being a mild algae killer.
I'd say with good CO2 gas, adding GA might be detrimental.
Plants adapt to GA over time.

While it might be nice to know.........the answer to some of these questions, I suspect it'll be a long time coming.
 
Ethanol as found in vodka and other alcoholic products has a chemical formula CH3 - CH2-OH. Plants cannot use ethanol directly. They can only use CO2.
That involves the oxidation of ethanol.

CH3CH2OH + 3O2 = 2CO2 +3H2O.

This reaction occurs easily if you heat ethanol and ignite it in air. That is the basis of flambe'. It is also the reaction that occurs in an internal combustion when alcohol is added to gasoline. The challenge is getting the oxidative reaction to occur at aquarium temperature in a aquatic environment. There are some bacteria that can oxidize alcohol to acetic acid. The intermediate step produces acetaldehyde. Acetaldehyde has the structure CH3CHO. Glutaraldehyde, which is the chemical in Excel, is a dialdehyde that has the aldehyde group at both ends of the molecule. It has the structure COH-CH2-CH2-CH2-COH.

Aldehydes can be further oxidized into CO2 and water if the proper enzymes or catalyst is available. Human bodies have the necessary enzymes to break down both alcohol and acetic acid (vinegar). Presumably, various organisms in the aquarium can do that as well. Whether the proper enzymes are available to break down glutaraldehyde is unknown. Apparently, Seachem believes they are. The challenge is getting the enzymatic reactions to occur at a rate that will provide a suitable concentration of CO2 to the plants. Tropica believes that this does not work.

Rather than using vodka or glutaraldehyde to produce CO2, you might want to consider setting up a DIY reactor to produce CO2 through the fermentation of sugar by yeast or the reaction of vinegar and sodium bicarbonate (baking soda) to release CO2 from the bicarbonate.
 
I tried keeping dwarf baby tears and some delicate mosses with aqueon leafy green, for about 3 weeks before I got my co2 up and running. What you'd expect happened, I saw like 70% of all of the more delicate plants die off, the sturdier plants did fine and grew a lot, but everything is doing better and growing healthier with the real co2 gas. The baby tears held up better than the moss for sure, but they both lost a lot of mass. Never had a problem with algae, although im not sure if the liquid co2 is to blame or the fact that some snail eggs hitched a ride on my plants, grew up, and established themselves as my free cleaning crew.
 
Advertisement



Advertisement








Advertisement




Back
Top Bottom