CO₂ Vs no CO₂ grow test

I have setup two tents, one with CO₂ and one with normal atmospheric CO₂. All other factors are the same, clone plants, grow light, humidity, temperature and nutrients.
The grow will be run until the plants and chillis are mature. Let me know what you think of the setup.
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[@davideckstein6692]

The plant will grow at a higher rate with just CO2 added but to get to 30% more growth you have to add more lights and more nutrients

[@MrBoho7]

Thank you for working with field respected experts. You implement the changes you learn into your products, and I like that

[@PhillyJuggalo]

Hey Shane first off I hope your having an amazing month so far, but I was thinking what if you made a CO2 video where you try out different ways to provide CO2 to the tent for instance like mushroom bags vs tanks and so on, then we could truly see which is the best for a grow tent and which even stays the most consistent. Have a great month everyone, Namaste.

[@MIGROLIGHT]

Hi, thanks. Good idea. I will test the mushroom bags and other systems and compare

[@garrygrant8511]

That would be a great comparison.

[@concreter6832]

​@@MIGROLIGHTmushroom bags are useless in tents from my experience.the small amount of CO2 U make goes straight out the exhaust fan ,with a tent U have passive air flow U don't need supplemental CO2 or unless running a very powerful light ,CO2 is for sealed rooms ,

[@dannyc6166]

I was going to do this test myself, but I think I’ll wait until the end of the series. Great experiment Shane!!!!

[@Humbulla93]

​@@concreter6832CO2 in a vented tent in general isn't worthwile, also CO2 should be added If you reach the saturaion point of lighting at around 1200PPFD then the added CO2 will have an effect

[@stangmann1521]

Co2 is good for big grows of 50+ plants, but in a "Home grow" tent etc. / it's going to be vented out when your fans adjust the VPD - the heat & humidity! Just spend time in the grow & my CO2 shots way up! So, no need to waste your $$$ on CO2 in a tent or vented room!

[@timpage5021]

Agreed.. That’s been my experience too. Large scale . Small home grow no.

[@polakmay3888]

Good test , looking forward for results.

[@Eric-dz1we]

Thank you, Shane. This is perfect for me. I've been questioning doing this myself. You really do so much, and for us to.

[@softaco3088]

I've always used co2 in my planted aquariums, i didn't know this was a thing outside of the aquascaping community. Very cool

[@mikebird8290]

Hi Shane looking forward to watching the test thanks Sir. Have a great weekend 💚✌🏼🤩

[@paulopoint0]

Whaou.. good job shane! Happy to follow your experience again.. Nice day bro! 🔥🙏

[@JasonJCWright]

Thanks for all your great work Shane!! 😊 Can’t wait to see the results from this 🤓

[@tacosforus1688]

Really cool set up! Excited to see the difference

[@tonyfanfarone]

Excellent content as usual. About to push the button on an array 4 and uv set for a 2×4 tent that I also don't have yet. Need to purchase piece by piece for a grow project with my son. Should be fun and very interesting. Have a good weekend.

[@dmo848]

Very therapeutic something I didn't think I would get with growing.

[@camz1039]

Love these comparison tests Shane!

[@the_gold_canopy]

I use tank fed Co2 in my 4X4, it is done with a balancing act of fresh air, air circulation, humidity, temperature, and timing, turning on both UV lighting and Co2 simultaneously for peak hours. Best additions for a perpetual harvest rotation, and definitely makes all the difference. Quality controller/monitors and regulators also make all the difference, and it's definitely cheaper to get your tanks at a welding gas supplier vs grow shops.

[@stogie525]

Thankyou for taking the time to make these videos, very interested to see the results.👍

[@BleachDemon99]

Could you throw one of those exhale bags in the tent without c02 for 24hrs to see if they actually make a difference and worth the £40 🤔 thank you for your knowledge 🙏🏼

[@JaSon-wc4pn]

Love the airated pots Looks futuristic

[@chenkarp]

Co2 intake is directly correlated to light intensity. So you should look for various light levels rather than Co2 level.

[@thematronsmilitia]

One of the most important effects of co2 is that it increases photosynthetic efficiency at high temperatures, and high temperatures accelerate biochemical processes

[@cinedan5497]

Cool experiment, but I always thought that added Co2 just allowed the plants to tolerate more light which allowed more photosynthesis, hence more growth. The Co2 alone, with all the same conditions otherwise I wouldn't think would do much for the plants. But I guess we'll see.......I will definitely be following this one.

[@twistedsocal]

Typically you don't want to add CO2 until flower and also usually with CO2 it allows higher temps without stressing the plants

[@UbiquitousRomp]

During the vegetative stage, when the plants are growing leaves and stems. At this stage, the plants are not yet producing flowers, so higher CO2 levels can help promote vegetative growth... which increases the root mass ready for flowing stage.

[@jahroen]

hi shane , i advice you to put a drain tube on the dehu . the water collecter is a hassle to remove when full of water

[@MIGROLIGHT]

Thanks, I have been through two cheap ones already and not impressed with the performance. I am going to return this one and get a better one and drain it as you advise. take care, Shane

[@ronin7261]

@@MIGROLIGHT You could also use a condensate pump for home AC units -- once the water flows into a mini float tank it is automatically pumped away as needed. Gravity feed to drain is best but the condensate pump works well for areas that have height issues or no drains nearby. My condensate pump moves the water from my dehumidifier roughly 3 meters vertically and 10 meters horizontally to a nearby drain line.

[@UbiquitousRomp]

@@MIGROLIGHT Get an app controlled dehumidifier...much easy to zone in a sealed tent with.

[@TheSnowbo83]

I used the AC Infiniti with the AC Infinity plug for my humidifier in dehumidifier works amazing just have to have a humidifier or dehumidifier that will turn on with being plugged into the wall without a button being pressed

[@timpage5021]

Be interesting to see the results. I’ve done a couple comparisons and the yield was marginal. Not really worth it. Maybe on a large scale it would be worth the squeeze..

[@UbiquitousRomp]

I think a lot of people can't get the high VPD in a sealed environment, so plants aren't transpiring as much as they should be.

[@martijnstam6186]

Once your plants are mature you want to water them every 2 days with some runoff that the plant must uptake in 24 hrs. Most people water when the soil runs dry which will hugely reduce plant growth.

[@laurentcassian3401]

Doing this with coco coir and synthetic nutes is a highway to pH troubles and nute burns. Kids, don't do this at home! High frequency fertigation with 10-20% runoff that goes down the drain, or a flood and drain setup that is sent back to a reservoir, then adjust ppm and pH is the way to grow in coco.

[@sinenomine4540]

For me this seems to be the hardest part in indoor growing. It's just too easy to overwater.

[@LibertiesDefender]

Love what you do. Thank you brother.

[@UbiquitousRomp]

I find as soon as my girls are big enough, I swap to but chugging. As feeding from the bottom, helps to keep down the humidity in the tent especially in a sealed environment. As the shop temps lower in the next few months. your tent temps will also drop a bit. which is going to decrease you VPD and would make it to tropical for flowering of medicinal plants, that need to transpire more. VPD aside. your going to need more air movement through the canopy when they bulk up to avoid rot as you're running such high humidity levels in the sealed tent.

[@MIGROLIGHT]

Thanks for the tip

[@Zer0Tolerance0]

Your phenomenal use of [butt chugging] really helped me visualize the process by using terms I'm familiar with. Thank you 🤣🤣

[@amitsinghjeer3921]

Been using it for over a year, C02 has been the difference when keeping the canopy from burning.

[@amitsinghjeer3921]

Ideal for leds and the uv bars

[@MIGROLIGHT]

Can you estimate the increase in yield you get?

[@bradg1226]

​@amitsinghjeer3921 did you notice an improvement in quality with co2 compared to healthy grows without co2?

[@amitsinghjeer3921]

@@bradg1226 yes, I found it produced a much denser and terpier quality but like I mentioned before the led add on bars contribute to this too. Even under hps it gave denser fruits, I've used all three mediums and CO2 enhanced each of the mediums know qualities, it's is definitely a must and you don't need to have ac either.

[@bradg1226]

@amitsinghjeer3921 will be my first run with led after many moons of hps. Im thinking uv addon and maybe a mushroom bag though the later stages of flower. Still i chose to start light with max 1000 par strength so not to burn anything. Baby steps haha

[@kittywampus]

A hanging dehumidifier 😮 why didn't i think of this before?

[@mattryan5372]

Put the co2 on a 12/12 schedule, only have it on during the day, because they release oxygen during the day. At night they release co2

[@ogricklamesa2609]

The light needs more Par output to benefit added co2.

[@nate6748]

love that hanging de-huey

[@xelo365]

Buen test, aquí atento a los resultados

[@davidchilderley]

Please can you include the CO2 bags like Exhale. Thanks.

[@artimusclydefrog]

co2 needs higher temps/humidity and light intensity to make a difference

[@MrMymorph]

I was under impression, that you'd need more light to make use of co2, so be very curious too see how this results

[@MIGROLIGHT]

Apparently CO2 will increase yield all other things being equal, except nutrients which the plant will take up more if it grows faster

[@MrMymorph]

@@MIGROLIGHT we will see soon enough. 🤩

[@graemebuchan1919]

@@MrMymorph looks like you may have been right

[@Eric-dz1we]

This test is also going to be about the par level, which is interesting not to buy a 1000w light 🤔. Shane, you are the man dog.

[@davideckstein6692]

In order for the CO2 to give you extra mass you're supposed to give extra nutrients extra heat and extra light because the plant can now take that with the CO2 that's the main reason you get extra plant extra yield that's according to dr. Bruce Bugsby remember the plant will take more of all of that because of the extra CO2

[@lilbear19601]

Hadn’t heard that about the heat.

[@lilbear19601]

But I know next to nothing about growing.

[@UbiquitousRomp]

That becomes more evident in later veg and flower when the plants get really hungry for the extra nutes. I used to grow at 78f But now I aim for the leaf temp of 82F which is about 84f tent ambient temp with my LED. Even without the Co2 running they drink much more in higher temps on a raised EC of feed. Got to remember to dial it back down though when you lower temps or cut the extra Co2 or the plants will choke.

[@IrlamOz]

If millions of growers are letting off co2 what does than mean for the real environment ? Dont get me wrong i have nothing against anyone doing the best they can for their ladies but whats the big picture i feel somewhat perplexed

[@fdsknjlsfnubk3e7hi8sx]

the big picture is the co2 was already here and doesnt change anything

[@IrlamOz]

@@fdsknjlsfnubk3e7hi8sx plenty trapped in the ocean and arctic ice science says

[@esk8spirit362]

Every tent is always being vented so it would be nice to see if there is any difference when the fan would be on

[@jasontran4525]

I love this experiment but I'm scared that your results could be tampered with possible co2 bleeding from 1 tent into the other. I'm following all the way still!

[@bobroberts9306]

I had the same thoughts about possible co2 bleeding since the two tents butt tightly together. If possible, separate a few feet? Hope Shane comments with his thoughts.

[@MIGROLIGHT]

Hi, sealing of the CO2 tent is good but there will always be a little leaking. However the room the two tents is in is big and is ventilated. Surprisingly working in the room has a larger effect than the CO2 tent being beside it. The no CO2 tent is stable at about 600PPM CO2 and the CO2 tent is at 1300PPM so there is enough of an increase to demonstrate the benefit. Thanks for the comment, regards, Shane

[@danielschuller3142]

Left me hanging. does it help?

[@jimd1617]

super excited!!

[@senorbirdman2331]

Amazing! Thanks Shane!

[@MrBalisticNinja]

Im trying to decide between the Evo 8, Mammoth 6-bar, or the Migrow 5x5 for my 4x4 tent. I cant find much else for reviews on your Migrow 5x5, but for the price it seems great

[@germanquintana1610]

Excellent set up Shane,, thanks a lot for all the work and videos.🌶️👍

[@jcmusc]

I've been LOVING your Vs series! Great educational videos! In the future, maybe make a synthetic vs organic amendments in coco coir? 🤔. Maybe UV vs no UV supplementation?

[@tg8051]

Interesting way to hang your dehumidifier…how do you empty or drain it?

[@YessiYuri]

Thank you for the American conversion.

[@jonnycarrick7552]

Please can you price how much it costs to use CO2 and the cost to get set up .thanks Shane you really are doing awesome work and as a grower who can’t afford to just buy the new tricks I have to get as much information and save up to buy . Thank you

[@UbiquitousRomp]

I read a study a few months ago that said the CO2 molecules get smashed by the fan, so it isn't so officiant to put the tube behind the blades. It will also make the blade edges get gungy with a larger build up of crud... That made my fans more noisy. So I've gone back to just hanging above the canopy, the air movement from my clip on fans soon gets it spread evenly around the plants. Whats the vpd of each tent Shane? as it will show how humidity is relative to the individual tent temperatures, which some will fine interesting. On the sealed tent, how often to you open it up to do a fresh air exchange. Also what is the Max temp of tent with Co2

[@MIGROLIGHT]

0.56 VPPD, 28 DegC (82F) and 70 % humidity

[@kaiglasenapp2395]

Bro u good? 😂 Seriously you just solved global warming, just put some fans outside and it will smash all the co2. You really made my day, thanks ❤

[@UbiquitousRomp]

@@kaiglasenapp2395 I didn't say all of it....I said that it reduced the efficiency. Which it does. You can believe it or not...the study isn't too hard to find. or the extra crud on the fan blades it causes. Thats the gas going back to liquid form. As the blades bleak down some of the co2 molecules. removing the outlet from behind the fan stopped the large build up accruing. Something else you will find pointed out on Co2 forums if you bothered to look, instead of making smug ill informed comments. as your only contribution to a complex subject. PS who told you that the worlds current ambient CO2 levels of about 400ppm was causing global worming.? They lied to you. as a gardener you should know this.

[@UbiquitousRomp]

@@MIGROLIGHT "28 DegC (82F) and 70 % humidity" ...Gives a VPD of 0.9 Shane. You'd need for the temp to drop below 70f with humidity at 70% to get a low vpd of.0.5. Thats more of a lights out figure.

[@kaiglasenapp2395]

In case you are not trolling: what you are telling is high quality bs. Co2 is only liquid under very high pressure or very low temperatures. Both not present in a growing environment. Also you said the blades would smash co2. That is a self contradiction you did there. If you are naiv enough to belief a study saying that fans smash co2, you are the one, that should provide the study. Also you can call my comment uninformed. but from someone like you, who thinks as a gardener I should be aware that co2 is not a reason for global warming, I think it marks my comment as valid. I don't want to be personal, but what you said here is really not intelligent.

[@dalelane1948]

I run my exhaust/carbon filter 24/7 to control humidity, I can't see how I could use co2 unless I kept my (large ) lungroom at that level I dint see how I could implement it. Anyone have any ideas for high humidity environs?

[@daytripper7879]

Can you use air-cooled reflectors? If so use your extraction fan on the lights to deal with temperature and a dehumidifier for the humidity. You wouldn't need a carbon filter either because the exhaust air never comes into contact with the plants just the lights

[@UbiquitousRomp]

You have a dehumidifier in the lunge room. But that's expensive. You can get away without one in veg.....but once you have a see of green, you'll nee to dehumidify. or just opening up the lung room every few hours and letting out the humidity. The higher temps allow for higher humidity. So at 80f + your fine with humidity levels in the 70+'% range. But you'll end up with damp on the walls by your lung room window.

[@ConsciousnessLivesOn]

Will CO2 be higher growing in a shed covered in foliage in a garden surrounded by trees & plants?? Thanks for experiment.. this will be interesting 👍😁

[@redeye1773]

theoretically it would require a higher ppfd and nutes to accommodate the added co2

[@TheSpeechkiss]

lovely setup

[@benharrup5797]

GOOD work Shane 🤙🤙🤙🤙

[@ManicMindTrick]

Why would you go to this length and expense to grow...chilli?

[@melangkoh4184]

hello shane. what would happen if you put a couple of candles/teelights in the tent? i read that 2 candles produce as much CO2 as 1 human. Would be great if you could make a video on that, you do have all the equipment set up. Its potential fire hazard, but it can be set up in a pretty safe way if you put soem thought into it.

[@dmo848]

Make a can of CO2 with yeast and sugar😊water. Boom what a thought

[@radimmanak4388]

It would be better to have a normal CO2 level of 400 ppm, which is the typical CO2 level in the atmosphere, compared to elevated CO2 levels of 700-1200 ppm. I believe that there wouldn't be a significantly large difference between 700 ppm and 1200 ppm.

[@radimmanak4388]

But I'm definitely looking forward to seeing what results it will yield; this really interests me a lot.

[@gasketguyal]

this is a cool but expensve experiment. no one uses those tents to grow peppers though..

[@mcbrite]

Do you know how buying straight CO2 compares to buying citiric acid and baking powder and use it in one of those stainless steel CO2 generators? I could get 25kg EACH for 100 Euro total...

[@davideckstein6692]

Actually it's not that the plants use more heat when you're using CO2 is just that they will handle the extra heat that comes along with all the extra light you're using. Basically the extra CO2 gives the plant the ability to handle more nutrients and more light there for more heat also

[@MIGROLIGHT]

Well said, thanks

[@markrich3271]

Wrong plant in my case but I'm interested....I have a regulator and controller but no bottle.

[@anothertormentedsoul]

Awesome work, thanks for sharingg

[@Eric-dz1we]

So, the tent without co2, how are you controlling your temp and humidity, and what numbers are they running compared against the co2 tent.

[@bigdillan9612]

I don't think you'll see a difference between small plants as they won't be mature enough to make use of the extra light which gives the need for the extra C02 in photosynthesis. Maybe running this again with fruiting tomato plants would give a better comparison.

[@MIGROLIGHT]

I will be running this test right through to harvest

[@ethansanders1926]

I would try and not have the fn blowing right at the leaves because the leaves need time to uptake it have the co2 fan at the very bottom

[@Memflix]

How many kg is that co2 cylinder and how long does it last keeping the co2 at 1300ppm?

[@ClintonBallinger]

I've never seen a cannabis plant with that leaf structure before.. Hm must be one of those stealth crops.

[@ghostmane2643]

Lmfao I thought I was the only one crazy enough to hang a big ass Dehumidifier from the top

[@laurentcassian3401]

wait..! have you really hooked up the dehumidifier from your tent's structure!!?? Damn!

[@fastnbulbouss]

I have a question concerning this method. How can you use an air extractor with a charcoal filter if you're adding CO2 inside the tent ? Wouldn't it make the whole thing useless ? Not to mention very expensive .

[@kaiglasenapp2395]

The problem is not the carbon filter. Carbon will not filter co2. But the extraction system will blow the co2 out. So you would not want to oversize your extraction system, as it is often suggested, if you are using co2

[@MIGROLIGHT]

tent is sealed, not need for charcoal filter

[@fastnbulbouss]

@@kaiglasenapp2395 I know the problem isn't the filter, but the extraction system. What it seems to me,, but correct me if I'm wrong, is that all that CO2 thing, seems a lot of trouble for little results.

[@theNZmatt]

Hi, is that silver cloth tape you have used to seal the vents on the tent?

[@skyridercommendor6303]

Sorry to say this, butt we dont need more cO2 uuse at alll 2+2=4 what will this doo to the clima 😢

[@barcaisbest10]

I think CO2 fed plants benefit from having higher temps. Or is it that plants can handle higher temps with CO2? 🤔 I know I read somewhere that there is a relation between the CO2 levels and temps the plant is experiencing. Also what is the PPFD level on the ones with CO2? I believe they usually match the PPFD to the CO2 no?

[@wardaldo69]

My knowledge tells me for added co2 to be as effective as it can be the temperature should be raised 🌱 👀

[@MattLind-oi5kg]

Science! Lovvit, cheers.

[@Shinika01]

epic experiment once again! Looking forward to follow this one ;) Great set up

[@CANNABISfreedomNOtaxes]

Ive never seen anyone use CO2 in a tent. I think its pointless unless youre running an actual grow room that is sealed with extremely high PPFD. CO2 best supplements hydroponic grow systems such as rockwool, DWC, or aeroponics. You will see far better gains in a hydroponic system than you will with soil or coco. CO2 tanks work great until you reach a space that is roughly 1000 square feet, then its best to use a burner system that converts fossil fuel to CO2 if youre going larger than that.

[@RicketyKrickett]

If you have an exhaust in your tent doesn’t that suck out the co2?

[@DJTHRILLER]

What’s a good way to seal the tents? I wanna use it on my grow but I’m not sure about the sealing part and how to do it. Thanks

[@user-jv2rk5vf5v]

He is reffing to boosted Co2 Vs. Ambient levels …..to clarify

[@phill3144]

What about the vpd, what number is that at, cheers

[@MIGROLIGHT]

0.56 VPPD, 28 DegC (82F) and 70 % humidity

[@UbiquitousRomp]

@@MIGROLIGHT Thats wrong...the correct figure is 0.9 on those numbers Shane

[@staceymcdermott4954]

What inline fans is used in this setup seems decent quiet

[@davideckstein6692]

The CO2 allows the plant to use more life more nutrients more heat more of basically everything that's the main reason you can get more of everything out of the plant

[@MurdahBassRecords]

Obviously 😂🤦‍♂️

[@wowa0309]

Hey how do you keep your humidity without a humidifier?

[@bradg1226]

Im guessing as long as you have between 700-1000 par, only yield increases with added co2 and par, not the quality?

[@UbiquitousRomp]

As the ambient is only about 400. unless you are going in to the grow space often or are drawing in air from an inhabited space thats producing Co2. supplementing to meet the higher levels of photons, will produce more photosynthesis. Which will increase yield and keep the plant leaves and flowers healthy if the nutes levels are matched.

[@AutoBudz]

Co2 is needed for large grow operations but for small closet home grows its really a waste of money. I mean if you want one of those Exhale bags or something go for it i guess but its not needed in my experience. I noticed no difference growing in my 2x4 and 4x4 with and without co2

[@damanichildrey84]

What's the white unit you have hanging? Is that necessary

[@hatz11]

Does adding CO2 to the tent effect temperature in the tent?

[@gtgrandad888]

Good day to you Migro, I want to purchase your LEDs but not sure which one would fit my tent? my tent size is 120x120x200cm.

[@zackmorisco1854]

Watch out you dont wet the co sensor. Better to hang it just above the light.

[@UbiquitousRomp]

sensor should be around canopy level as Co2 is heavier so hangs around lower down.

[@DeathbyKillerBong]

thats gonna be intresting

[@Unkdunk]

Wayy too much gear ,The hanging dehu did it for me 🎉 4 out of 10. Plant killer....interesting video though still subbed

[@jasonpavlak2055]

Is that what I should be doing?, is looking for a smaller dehumidifier to put inside the tent(I love how you hung it) instead of a very powerful one on the outside of the tent. Whats the brand of that dehumidifier kind sir? Thanks Shane

[@MIGROLIGHT]

It seems the most efficient way to me. However I have tried two relatively cheap ones to date and they are not great, running all the time. I am going to return them and get a better one

[@UbiquitousRomp]

@@MIGROLIGHT Do you think having it in the tent will dry out the coco quicker?

[@eggspanda2475]

cool bananas .

[@danielcollins9628]

Does anyone burn candles for co2 supplementation

[@АлексейНовиков-ь1о]

Flexstar Nova !!! Test ???

[@tibbsmcclane7857]

Is this Coco coir?

[@bennystokes8481]

hi shane what ppfd range should we be aiming for when growing seedlings for 3 weeks before transplanting and flipping? without co2...

[@MIGROLIGHT]

Hi, about 250 PPFD is perfect for young ones. This will usually be at about 30 to 40%dimmer settings at standard grow light hanging height

[@UbiquitousRomp]

Start at 250 and work up to 400 -500 before flipping. but watch your leaf tips for over burning. If your leaves look droopy and it's not a watering issue, then it can be to much light. As you go up in power, just keep checking.

[@bennystokes8481]

im using a mix of 5000k t5s and a lumatek x40 flowering bar..i didnt go for the veg spectrum as it was mainly blue with about a 3rd red..i hear blue light is inefficient for seedlings..ive got 24 watts of 5000k led and the lumatek pushes out around 110 ppfd..not sure what the 5000k led pushes out being a full spectrum white light.@@MIGROLIGHT

[@UncleChud]

Get the water outta the tent,lower humidity.

[@charlesfield9286]

Just putting a mouse in a cage would be a way cheaper way to add CO2. Or maybe a bird.