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CO2 for large tanks

2730 Views 25 Replies 11 Participants Last post by  2wheelsx2
Hi !

I just got into a debate with someone who claims that CO2 is not necessary (at least for the large tanks). I have no reason to believe that this person is knowledgeable, but I should give him a benefit of a doubt. I personally only have experience with CO2 with small tanks (under 30G) and I don't have experience with larger tanks.

So, to disprove this person I went to AGA contest page to see what tanks list CO2 in the tank info table and to my surprise very few tanks mention CO2. This could mean one of two things: (1) CO2 is indeed unnecessary or (2) CO2 is as obvious as water, no point in listing something this obvious. Which one do you think it is ? In particular it would be interesting to hear if folks who read this forum and submitted their tanks to AGA contest listed CO2 in tank info.
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How large is "large"? Tom Barr's "Behemoth" uses CO2 and I believe it's 1600 gallons.
The plants know no difference between a large and small aquarium. Many plants will grow without the introduction of CO2, but they will grow much more slowly. There are many people who prefer "low tech" tanks with lower lighting and little or no CO2 as they require much less maintenance. Adding CO2 will dramatically improve the ability to grow plants in large or small tanks, and I would venture a guess that most AGA entries used CO2 and simply did not list it because it is so common.
2wheelsx2, by large I mean anything more then 50 gallons or so. I am a small scale guy :)

aquaman3000, thanks for your opinion ! It's no surprise to me that my friend who stated that CO2 is not necessary doesn't know what he is talking about :)
2wheelsx2, by large I mean anything more then 50 gallons or so. I am a small scale guy :)

aquaman3000, thanks for your opinion ! It's no surprise to me that my friend who stated that CO2 is not necessary doesn't know what he is talking about :)
its not necessary, if you add higer lights (more then 2.5 wpg) and dose fertz, its just another building block on the way to being able to grow whatever you want, but some plants will do just fine with out all of that.
Agreed, it depends on the amount of light, not the size of the tank. Size is irrelevant.
I only mentioned size of the tank because I have first hand experience with smaller tanks (<50G), but I have never tried anything bigger.

The tank that we were discussing is 130G with about 300W of T5 light. So, we were arguing if it needs (would benefit from) CO2.

Something that really surprised me is that AGA contest tanks don't list CO2. So I was wondering if I really missed something and those folks really grow such beautiful setups with no CO2 injection.

Thanks for the replies !
No CO2 Large Tank?

Someone else ask the question, what is "Large". Considering most average home aquariums, I suspect 100+ gallons as large ?

If so, the answer is yes. You don't need compressed co2 to have a good looking growing tank. I owned and maintained a 125g for a number of years without CO2. It's about balance. The right amout of light and livestock and plants.

6 Years later, I downsized to smaller tanks and use a combination of compressed CO2, "electronic CO2 -carbo Plus, and DIY co2. I have been around doing aquariums for 30 years.

Compressed CO2 and proper lighting offer superior results, but takes more effort. My compressed CO2 system is controlled by both PH and timer. So it works when needed and the lights are on. Plant growth is speedy and hence more work. You make a mistake in the high tech approach, things go bad fast.

The no co2 appraoch works and is like "slow motion" and lower maintenance and slower growth - but works fine.
Most people want instant gratification, with compressed co2 you have a head start but must watch a number or parameters.

My recommendation, invest in a compressed CO2 system and good versatile lighting, start slow on the CO2. Once you learn lighting and co2 control "You can dial in the "speed".

From my experience, most overstock fish in a early rush to sucess, leading to algae problems. Try plants first with a slow introduction of fish.
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While size does matter in most cases, :hihi: not in this case.

There are plants that grow without it, and plants that absolutely require it and everything in between. The size of the aquarium they are in has absolutely zero bearing on it.
The key word to the entire debate is: Necessary.

Necessary--being essential, indispensable, or requisite

The addition of C02 is not necessary. But C02 is. So, Your friend is right. The lighting on any setup can be lowered/adjusted to make the addition of C02 UNnecessary.

If You want to talk about whether or not C02 is necessary with X-amount of light--that's a different issue. But technically, the addition of C02 isn't necessary, so, technically, your friend is right.
So, I guess the second part of my question is - why do AGA contest entries do not list CO2 ? Is it not used in those tanks or is it just obvious ?
Personally--I don't know, but honestly--I think its a combination of the 2.

Seems that many of those beautiful tanks are much lower tech then is inferred by looking at them. Not all, but many....:thumbsup:

My thoughts anyway......:icon_roll
look at nature. There is no pressurized C02 being added. I personally believe people use C02 and ferts to speed up growth, nothing more nothing less. All of the beautiful tanks you see where the people use C02, they do so for "instant" (more or less) gratification. I personally believe the same results can be achieved without adding these things. IT JUST TAKES MUCH MUCH LONGER.

So, in other words, I agree with your friend.
Nature is a not a closed system. Is it possible to have a beautiful tank without CO2 and ferts? Sure it is. It's also possible to have one without ADA AS, 3 WPG lighting, filtration, heaters and water pumps. But we are working with "closed" systems here. How often do you see the flora/fauna density in nature that you see in our planted tanks?

CO2 is just a tool, it can used and abused like anything else.

An equivalent analogy is that you can build a house with hand tools, but it's sure nice to have power tools for the big jobs. :p
Co2 ?

fshfanatic vbmenu_register("postmenu_488860", true);
Wannabe Guru

made a good point. You don't need C02 to have a good looking tank.
For you old timers - You can't fool mother nature....

Everyone here makes a good point.
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So, I guess I'll rephrase my question again :) : do you think the best tanks (ADA and AGA contest tanks) are done using CO2 ? Even if every single one of them *can* be done with out I am wondering if there is any information about what was actually used.

In general I understand everyone's point(s) that it's not a deal-breaker, after all as 2wheelsx2 pointed out one could build a house with ones bare hands and simple tools. Yet all housed nowadays are build using power tools. So, I am wondering if planted tanks nowadays are done using CO2.
I would venture to guess that yes all those ones you speak of are using CO2
look at nature. There is no pressurized C02 being added.
Nature also doesnt try to eliminate algae, in fact, it seems quite abundant in nature :wink:. Despite what many think, most of our high tech beautiful planted tanks really arent all that natural, but they sure look great.
I would wager that most if not all of the AGA contest tanks were done with CO2 because you have a year from one contest to the next to get your tank done in time. Here is an example of a beautiful tank with no CO2:
do you think the best tanks (ADA and AGA contest tanks) are done using CO2 ?
Emphasis added.

I would agree that most of the ADA/AGA tanks inject C02. But "the best tanks" is like the top 10, 20, 50, even 100 (to me anyway). This discussion has been had before, I guess you'd be surprised how many and which tanks are low light, low tech.

Some are, some aren't--and you really can't tell them apart by looking at them. That was my point earlier.....
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