Co2 Facts. Please

[grbudman]

I ran into someone, and we are debating 1 point: when is the best time to introduce a CO2 tank? during veg or flower?

[Nemosity]

Personally, I would only vent COz while flowering. It may help make the plants bigger in veg, in a shorter time, but the real rewards for using COz is when your flowering. Just my $.02

[bobandtorey]

i have used it and it does work but you don't have to have it if you got the money then good use it in flowing

[THC-Farmer]

I always recommend to simply keep a decent air flow and/or a nice air exchange setup, as it is far more cost effective.

 

1500ppm or higher is the general rule of thumb if you choose to use C02 supplement. This amount of C02 concentration is the most effective as it gives the highest growth rate possible with as little C02 production as possible.

 

However, it's a lot more difficult to use C02 effectively as it must be monitored and used strategically or it's a complete waste of resources...

 

The only benefit to adding more C02 to the air is a slightly higher rate of transpiration. This of course translates to a faster growth rate for vegetation. So more CO2 means faster plant growth.

 

HOWEVER, this in turn increases the requirement for higher moisture levels at the roots but lower humidity levels in the air. It slowly becomes a tricky situation and can actually become a negative situation if moisture levels are not monitored and adjusted accordingly.

 

In my honest opinion, based on my experience and the scientific data available, the slight growth rate increase does not justify the cost of C02 generating equipment.

 

For those who say they have seen huge increases in yield with little yeast bubblers and C02 generators, prove it! Show us the side by side blind tests with the results. Because I have done multiple tests with C02 and none proved worth the effort by any means. I never experienced any major yield increases during my trials. Any yield increases I did recieve could be attributed to many other factors as they were very very small differences. And all the current scientific data suggests and directly implies that the only benefit of added C02 is increased growth rate.

 

I'm not saying C02 isn't beneficial. Of course it is! Don't get the wrong idea here... I'm just passing along the logical notion that EXTRA C02 is not necessary at all. Providing, of course, that normal C02 levels are already present (300-400ppm).

 

As long as you have nomral C02 levels you're going to get perfectly normal growth rates. If you don't have normal C02 levels then you may need to think about a solution to that problem. A lot of times it's cheaper and more efficient to simply create a ventilation system to exchange air on a timed basis.

 

The increase in C02 levels really doesn't increase the growth rate as dramatically as one would hope. Though, there is no denying it, extra C02 will indeed increase the growth rate. But that's all it will do. Whether that will help you or not, is your decision. For bumper croppers I can definitely see a benefit for the use of C02 throughout the entire grow because faster growth rates equals more harvests in a shorter period of time.

 

But for a simple medical cannabis grow, I really don't feel a whole lot of effort should be put into C02 production. It really is a waste of time. Even on a slightly larger scale if you were a caregiver with 5 patients. When you compare the increase in growth rate to the cost of increasing that growth rate it really makes you wonder what the point of it is...

 

Either way it's always one of those personal preference additions to a grow room.

 

Give it a shot!

 

Or save your money, let the God given free air do what it does best, and put your man made money towards better care for your medicine.

[HerbanLegendSeeds]

I always recommend to simply keep a decent air flow and/or a nice exchange setup, as it is far more cost effective.

 

1500ppm or higher is the general rule of thumb if you choose to use C02 supplement. This amount of C02 concentration is the most effective as it gives the highest growth rate possible with as little C02 production as possible.

 

However, it's a lot more difficult to use C02 effectively as it must be monitored and used strategically or it's a complete waste of resources...

 

The only benefit to adding more C02 to the air is a slightly higher rate of transpiration. This of course translates to a faster growth rate for vegetation. So more CO2 means faster plant growth.

 

HOWEVER, this in turn increases the requirement for higher moisture levels at the roots but lower humidity levels in the air. It slowly becomes a tricky situation and can actually become a negative situation if moisture levels are not monitored and adjusted accordingly.

 

In my honest opinion, based on my experience and the scientific data available, the slight growth rate increase does not justify the cost of C02 generating equipment.

 

For those who say they have seen huge increases in yield with little yeast bubblers and C02 generators, prove it! Show us the side by side blind tests with the results. Because I have done multiple tests with C02 and none proved worth the effort by any means. I never experienced any major yield increases during my trials. Any yield increases I did recieve could be attributed to many other factors as they were very very small differences. And all the current scientific data suggests and directly implies that the only benefit of added C02 is increased growth rate.

 

I'm not saying C02 isn't beneficial. Of course it is! Don't get the wrong idea here... I'm just passing along the logical notion that EXTRA C02 is not necessary at all. Providing, of course, that normal C02 levels are already present (300-400ppm).

 

As long as you have nomral C02 levels you're going to get perfectly normal growth rates. If you don't have normal C02 levels then you may need to think about a solution to that problem. A lot of times it's cheaper and more efficient to simply create a ventilation system to exchange air on a timed basis.

 

The increase in C02 levels really doesn't increase the growth rate as dramatically as one would hope. Though, there is no denying it, extra C02 will indeed increase the growth rate. But that's all it will do. Whether that will help you or not, is your decision. For bumper croppers I can definitely see a benefit for the use of C02 throughout the entire grow because faster growth rates equals more harvests in a shorter period of time.

 

But for a simple medical cannabis grow, I really don't feel a whole lot of effort should be put into C02 production. It really is a waste of time. Even on a slightly larger scale if you were a caregiver with 5 patients. When you compare the increase in growth rate to the cost of increasing that growth rate it really makes you wonder what the point of it is...

 

Either way it's always one of those personal preference additions to a grow room.

 

Give it a shot!

 

Or save your money, let the God given free air do what it does best, and put your man made money towards better care for your medicine.

 

 

Well said, I have grown for years without CO2 and my yields are just as good as those who use it. It can and will cut down your flowering time by a week, which in turn will give you another harvest per year.

[MightyMightyMezz]

Wow, so Co2 does not increase yield! Crazy. I thought it did. Then again, increasing growth rate would tend to increase yield, would it not? I mean you can call it cutting down flowering time, but if you let your plants go the same amount of time they would get bigger and you would have to call it increased yield. Increase your yield by 30% and you can probably pay for your initial investment in one harvest. Am I out of my mind?

[BDR]

Yeah, will not increase yield by any real noticeable #'s on average... Just speeds up growth rate, witch in turn will allow you to harvest possibly one or two more times a year..

[MightyMightyMezz]

Yeah, will not increase yield by any real noticeable #'s on average... Just speeds up growth rate, witch in turn will allow you to harvest possibly one or two more times a year..

 

So my eight week plant will be just as done at seven weeks with Co2 and will not grow any more if I let it go eight weeks?

[lkline300]

Carbon dioxide is absorbed by the plants and during photosynthesis the CO2 is is split into it's basic elements, carbon and oxygen. Small amounts of oxygen are used by the plant but most of the oxygen are released back into the atmosphere.The carbon is combined with water (H2O) in the presence of light to form a sugar molecule. The plants then convert the sugar into carbohydrates. When the plant absorbs nutrients (primarily nitrogen from the roots) they are combined with the carbohydrates to form new plant tissue. This process is called photosynthesis. The entire process is only as good as its weakest link. If any of the required ingredients (light, CO2, water and nutrients) are at a level below that which the plant can use for maximum efficiency, the plant will not perform at it's full potential.In other words, if you inject CO2 into a system that is not receiving enough light or nutrients the results will be disappointing. We here at Hydro-U recommend that CO2 injection should only be done by experienced gardeners with a good working knowledge of their gardening system. Once a gardener is comfortable with the workings of their system and plant growth, CO2 can be a great benefit, however there are a lot of variables involved with using CO2 and beginners can really have their hands full, increasing the likelihood of a disaster (like total death of the entire crop).

There are several conditions that must be met for the plants to be able to use the increased CO2 levels properly. The most important is lighting. Light levels must be very high (more than 20 watts per square foot) or there will be little or no increase in plant growth rates. The plants will like slightly higher temperatures than normal (approx. 3 - 5 degrees higher). The plants will also metabolize water and nutrients faster, so reservoirs may need a little more attention.

Plants can absorb and process very large amounts of CO2. There is usually about 300 to 600 p.p.m. (parts per million) of CO2 in the atmosphere. Most plants can use 1500 p.p.m. in optimum growing conditions. When using elevated levels of CO2 the growth rate can be increased by as much as 100% to 200%. Most studies report increases in the 40% to 50% range.

The ideal situation would be to keep the CO2 levels at optimum at all times. This would require constant injection of low levels of gas (constantly replacing what the plants are using). This is not practical in most situations as venting of the growing environment is often needed to control heat build up. In these cases CO2 injection should be done immediately following venting.

The biggest problem that people encounter when using CO2 is that they get carried away, they think that a little is good so a lot is better....NOT! When CO2 levels approach 2000 p.p.m. most plants will die. High levels of CO2 are also toxic to humans, primarily due to oxygen deficiency. Before injecting CO2 the room should be vented to remove excess CO2 that might be left over from the previous injection, this prevents the build up of CO2 that could harm the plants.

There are several ways to get extra CO2, the two most common are using bottled CO2 and using CO2 generators. These are the automated ways to add CO2 to the growing environment. Getting precise control of the CO2 levels in your growing environment can be rather expensive, CO2 monitors are the best method, these monitors keep a constant reading of the C levels and automatically adds gas when needed. These monitors are fairly expensive so most people opt for a more inexpensive method (like timers).

There are also several "low-tech" ways to increase CO2 levels. Additional information about using all these methods follows:

Using Bottled CO2

 

There are several ways to introduce CO2 into the growing environment. Probably the most popular method is to used bottled gas. This type of CO2 injection consists of a CO2 tank, a pressure gauge (monitors how much gas is remaining in the tank), a flow meter (to monitor the amount of gas being released), a solenoid valve (turns the flow of gas on and off as needed) and a method of controlling the solenoid valve (a timer or other controller). To insure that your garden is receiving enough (but not too much) CO2 from your bottled system, I have included the following charts (see below) that can be easily followed to determine how long you need to emit gas to bring the CO2 levels up to 1000 (first chart)p.p.m. or 1500 p.p.m.(second chart). Charts are supplied by Green Air Products.

Carbon Dioxide Flow Chart for Emitter Systems 1000 PPM (B) Flow in Cu. Ft. / Hr. (A) Cu.Ft.of

Area 10 15 20 25 * 30 * © Time (in minutes) 400 2.4 1.6 1.2 0.9 0.8 600 3.6 2.4 1.8 1.4 1.2 800 4.8 3.2 2.4 1.9 1.6 1000 6.0 4.0 3.0 2.4 2.0 1200 7.2 4.8 3.6 2.9 2.4 1400 8.4 5.6 4.2 3.4 2.8 1600 9.6 6.4 4.8 3.8 3.2 1800 10.8 7.2 5.4 4.3 3.6 2000 13.0 8.0 6.0 4.8 4.0

A. The cubic feet of the enclosure is determined by the formula (L x W x H).

B. Rate of flow as stated on the emitter regulator.

C. The time required to charge the enclosure expressed in minutes.

* NOTE: It has been my experience that if you set the flow meter up above 20 Cu Ft / Hr it can literally freeze up due to the cold created by the expanding gas. It is best to inject the gas slower over a longer time. -The Professor

Carbon Dioxide Flow Chart for Emitter Systems 1500 PPM (B) Flow in Cu. Ft. / Hr. (A) Cu.Ft.of

Area 10 15 20 25 * 30 * © Time (in minutes) 400 3.6 2.4 1.8 1.4 1.2 600 5.4 3.6 2.7 2.1 1.8 800 7.2 4.8 3.6 2.9 2.4 1000 9.0 6.0 4.5 3.6 3.0 1200 10.8 7.2 5.4 4.4 3.6 1400 12.6 8.4 6.3 5.1 4.2 1600 14.4 9.6 7.2 5.7 4.8 1800 16.2 10.8 8.1 6.5 5.4 2000 19.5 12.0 9.0 7.2 6.0

A. The cubic feet of the enclosure is determined by the formula (L x W x H).

B. Rate of flow as stated on the emitter regulator.

C. The time required to charge the enclosure expressed in minutes.

* NOTE: It has been my experience that if you set the flow meter up above 20 Cu Ft / Hr it can literally freeze up due to the cold created by the expanding gas. It is best to inject the gas slower over a longer time. -The Professor

Using CO2 Generators

 

Until recently CO2 generators were used primarily by commercial growers, but with the advent of smaller, less expensive units, many hobby growers now use generators. CO2 generators burn either propane or natural gas. They have a pilot light that ignites the gas when a timer has opened a solenoid valve to release the gas into the system (similar to a gas bar-b-que grill). The generators come in many different sizes.

Producing CO2 with a generator is more cost effective than using bottled CO2. The generators can produce aprox. 26.1 cu. ft. of CO2 per pound of fuel burned.

The generators work very well and are cheaper to operate than the bottled system, however, they burn the fuel so they give off a lot of heat as well as CO2. This may or may not be a problem for you. If you live in a colder climate and you need to add heat to your growing environment than a generator might be just what you need. If you live in a warmer climate you may already be battling the heat and adding more might send you over the top. With devastating effects on your crop.

Another word of caution about CO2 generators: If they are not working properly they can give off Carbon Monoxide (CO) instead of Carbon Dioxide (CO2). Carbon Monoxide is very dangerous! It is deadly even in small doses (CO2 is deadly too, but only in higher concentrations). You should only use top quality generators that have been built specifically for gardening and have been checked out by the manufacturer. When using generators make sure that the flame is burning blue, this means that there is complete combustion and the generator is putting out CO2 and not CO. If the flame is burning yellow or orange there is a problem with the unit. Turn it off immediately and do not use the generator until a qualified service person has fixed it! Yellow or orange flames mean that the combustion is not complete and the main by product will be Carbon Monoxide instead of Carbon Dioxide.

OTHER METHODS OF ADDING CO2

 

There are several ways to add CO2 to your garden that do not require a lot of expensive equipment. These are not automated so require more "hands-on" attention. Controlling the amount of CO2 is difficult at best with these methods, however there is little chance of accidentally adding too much CO2. Decomposing organic matter gives off CO2 as a normal bi-product of decomposition. Use materials like leaves, sawdust, manure, hay, etc.This method of generating CO2 is certainly inexpensive, with most materials being free, but it can be kind of gross. Besides being messy there is a possibility of disease and fungus forming in the decomposing material.

The fermentation process also gives off CO2 as part of the natural process (that's what puts the fizz in beer). Mixing water, sugar and yeast together will cause fermentation to begin and for CO2 to be generated.

Dry ice is solid CO2 that is made by compressing the gas until it "freezes" into a solid mass. CO2 is a rather unique substance in that it goes directly from a solid to a gas, which means that you can simply set a block of dry ice in your growing environment and it will slowly "boil" off CO2 gas. Dry ice is probably one of the most expensive ways to produce CO2 in your garden.

One pound of dry ice is equal to one pound of liquid CO2 (bottled). One Pound of either is equal to 8.7 cu. ft. of gas.

If you drip vinegar onto backing soda you will produce CO2 as well.

ADDITIONAL INFORMATION

 

If you would like to know more about using C in your garden there is an excellent book about it called "Gardening Indoors With CO2" by George Van Patten.

There is a lot of good information about CO2 equipment as well as other environmental controllers available at the following link. which is the website for GreenAir Products, which manufactures what most people consider the finest environmental controllers available for hobby gardeners. GreenAir Products

 

 

got this from GP

hope it helps. I have found that I don't really need it with proper exchange of air. I doubt I would see an increase of 30 % with it but I'm sure if I had every thing else perfect it would help. If I was to have an airight system , with no air exchange then It would be needed for sure.

[THC-Farmer]

Wow, so Co2 does not increase yield! Crazy. I thought it did. Then again, increasing growth rate would tend to increase yield, would it not? I mean you can call it cutting down flowering time, but if you let your plants go the same amount of time they would get bigger and you would have to call it increased yield. Increase your yield by 30% and you can probably pay for your initial investment in one harvest. Am I out of my mind?

 

If you want bigger yields you need bigger plants, more root space and more light...

 

Extra C02, beyond what nature provides, will simply make the plants grow faster. Nothing more.

 

Bigger plants will obviously yield larger amounts but the amount each different strain of cannabis will yield is limited by it's genetics. You can do everything possible to get to that genetic "cieling" but indoors it is extremely rare that growers actually reach a cannabis plants FULL genetic potential.

 

You need a ton of root space and the sun to do that. But regardless, even outdoors, you will not see any yield increases beyond what the plant is genetically capable of...

 

This is the main reason why I feel it's a complete waste of money for small personal medicinal operations. The plants are only going to grow as big as the indoor environment provides. Size limitations become an issue when resources like light and root space are limited.

 

But like I said before extra C02 WILL indeed speed the process up quite a bit. But if it's not done accurately the growth rate increases are very hard to justify when you compare it to the cost of the equipment. In my honest opinion the cost of the equipment to even attempt to do it correctly isn't even justifiable...

 

The best thing you can do with extra C02 is use it to help get the plant to whatever size you want it to be for blooming a little bit faster. All it does is speed the process up.

 

But no matter what you do the yield will not increase unless you grow bigger plants...

 

You don't need extra C02 to grow bigger plants... It takes more resources and more time to grow bigger plants though...

[THC-Farmer]

So my eight week plant will be just as done at seven weeks with Co2 and will not grow any more if I let it go eight weeks?

 

That is correct.

 

This is where genetic limitation plays it's role.

 

Cannabis is overall, nothing more than an annual flower. It goes through a natural cycle of life and death during a single season. Once the photoperiod has changed, the plant has changed it's metabolism and bloom phase has set in, it's pretty much a done deal...

 

The ONLY way to stop a cannabis plant from finishing that natural cycle is to increase the photoperiod again. Increasing the photoperiod during bloom phase will cause the plant to reset it's metabolic process and it will begin to "re-veg"... This will halt any further flower growth.

 

The genetics of each individual strain determines how long the plant takes to finish blooming.

 

If you speed the growth process up during vegetative phase all you're going to get is a bigger plant.

 

If you speed the growth process up during bloom phase all you're going to do is get it to its genetic limit faster.

[MightyMightyMezz]

If you want bigger yields you need bigger plants, more root space and more light...

 

Extra C02, beyond what nature provides, will simply make the plants grow faster. Nothing more.

 

Bigger plants will obviously yield larger amounts but the amount each different strain of cannabis will yield is limited by it's genetics. You can do everything possible to get to that genetic "cieling" but indoors it is extremely rare that growers actually reach a cannabis plants FULL genetic potential.

 

You need a ton of root space and the sun to do that. But regardless, even outdoors, you will not see any yield increases beyond what the plant is genetically capable of...

 

This is the main reason why I feel it's a complete waste of money for small personal medicinal operations. The plants are only going to grow as big as the indoor environment provides. Size limitations become an issue when resources like light and root space are limited.

 

But like I said before extra C02 WILL indeed speed the process up quite a bit. But if it's not done accurately the growth rate increases are very hard to justify when you compare it to the cost of the equipment. In my honest opinion the cost of the equipment to even attempt to do it correctly isn't even justifiable...

 

The best thing you can do with extra C02 is use it to help get the plant to whatever size you want it to be for blooming a little bit faster. All it does is speed the process up.

 

But no matter what you do the yield will not increase unless you grow bigger plants...

 

You don't need extra C02 to grow bigger plants... It takes more resources and more time to grow bigger plants though...

 

How does six gallon Air Pots and 1000W HIDs sound? I am pretty sure under those conditions and with temps hitting the mid 80's that adding Co2 would produce larger plants. Now I could veg with Co2 and cut down veg time or I could veg larger in the same amount of time which should increase yield considering it won't be rootbound and will have plenty of light. I could flower in Co2 and get a higher yield than if I hadn't I am sure. Why don't I do a side by side comparison? I can't really commit the resources. I'll just add Co2 and see what happens.

[MightyMightyMezz]

That is correct.

 

This is where genetic limitation plays it's role.

 

Cannabis is overall, nothing more than an annual flower. It goes through a natural cycle of life and death during a single season. Once the photoperiod has changed, the plant has changed it's metabolism and bloom phase has set in, it's pretty much a done deal...

 

The ONLY way to stop a cannabis plant from finishing that natural cycle is to increase the photoperiod again. Increasing the photoperiod during bloom phase will cause the plant to reset it's metabolic process and it will begin to "re-veg"... This will halt any further flower growth.

 

The genetics of each individual strain determines how long the plant takes to finish blooming.

 

If you speed the growth process up during vegetative phase all you're going to get is a bigger plant.

 

If you speed the growth process up during bloom phase all you're going to do is get it to its genetic limit faster.

 

Why are buds grown with Co2 denser? Have you noticed this? I'm pretty sure they weigh more per volume.

[jeff from bad axe]

CO2 should be used during veg. and flower at 1000 to 1500 ppm.During darkness no CO2.Yield increases by 30%.Any other facts are false.

[grbudman]

thanks for the help. have you guy seen the dry ice on you tube? supposedly the dry ice is like a pure form of CO2. basically add the ice to warm or hot water, and it will fog the whole room.