Candles for CO2?

[Crazy Horse]

Does anyone use candles for co2? As long as a guy is careful, is it worth doing?

 

[Hick]

I think that the number of candles required to produce any "beneficial" amount of co2, would produce a significant fire danger..AND excess heat.
If you're providing sufficient veltilation, co2 is waste anyway. co2 is really only beneficial, in a totally controled environment.

 

[Crazy Horse]

O.K. And Hick, like the new avitar lol!

 

[DankCloset]

i agree, c02 is a waste of time unless you have an ozone generator or something, anyway dry ice is a very safe method, along with brewers yeast, highest tolerance you can get. remember to put a nipple on it to control the release, if you do not have a grow room that will hold an ample room charge, then do not do it, and if ur growing pot indoors, u had better have ventilation or ur wasting your time preffered vent schematic: flow thru venting. or free cycle venting as you some call it.

 

[Head_Down_Under]

I can buy big bags of Tealight candles quite cheaply (the little squat ones in tin cases. They supposedly burn for 5 hours. Reading through this great site I've found nothing to help so let me ask:

1. Would a burning candle make an effective CO2 booster?
The extra candle heat and humidity would be welcome at the moment; its winter now in southern hemisphere and I don't get much heat from lights as they are all cfl and LED will be arriving in time for Bud stage.

2. Is extra CO2 more useful during veg or bud, or is it good for both stages?

3. Do candles give off other, noxious gases that could be a problem - like SO2 etc?

4. Would a burning candle help control odours (like the trick of lighting a match in the dunny to kill the smell if you've dropped a bad dump)?

5. If the demand is there and it all seems like a good idea then I can knockup and post a rough and ready formula for working out how much CO2 you'd get per candle - just let me know if you'd like one. But any other rough guides to getting CO2 levels right would be really welcome (changes in colour or shape of leaves etc might make useful indicators?)

6. Has anyone actually got real experience using candles for boosting CO2 in a growcupboard? If so I'd love to hear how it all went, good and bad stuff, if you'd bother again, have you got a better method than candles etc.

I quite like the idea of having a little ritual where I light candle each morning in the cupboardyshrine as thanks to the cute little plants agrowing in there for my future pleasure. So thanks heaps for the wisdom thats gonna flow my way from all you bright cool folk. On top of that unless I get a resounding "no way just don't do it!!" from experienced growers then I shall include candles in my grow which is about to begin, and I'll report back how it goes..

 

[Six]

Sounds like a dangerous way of supplying co2 but im only speaking as an opinion....no experience here...On the other hand, i have lost a house to fire in the past so im a freak when it comes to open flames...

 

[Shockeclipse]

Too dangerous IMO and if you dont have heat concerns you dont need it. It would prolly take 1000 tea lightw to even come close to supplying a benficial amount. How will your lights stay lit with ventalation fans going? To use CO2 efficiently your space has to be air tight. Don't do it, if you have proper ventallation then your plants are getting plenty of co2 and you'll just end up burning down your house.

 

[dirtyolsouth]

DON'T DO IT!!!

Keep your candles around the bath tub and in the living room to use only when you're present... Candles can cause some dreadful heat issues with your grow! Just give them plenty of fresh air... I used to lug around cylinders of CO2 for years before I got tired of it and stopped... The truth is I grow MUCH better bud now than I ever did when using CO2 injection cycles although it's more due to other factors... mainly ventilation and A/C. In the first few years of growing I thought that a major key to dankness was to supplement my garden's CO2. If you have adequate ventilation they'll get all the CO2 they'll need for healthy growth. A powerful inline fan pulling air out of your grow space will bring lots of fresh air with CO2 into your bloom space even if it's a tiny closet or grow box... If your flower temps are in the 70's and you have good ventilation you'll be batting a thousand in no time!

Good Luck!

 

[The Hemp Goddess]

No, the amount of CO2 would be insignificant. If you are exchanging the air in your space 3-4 times a minute, your plants are getting enough CO2. If your CFLs are not putting off enough heat, I am guessing that you do not have nearly enough of them. How big is your space and what lights are you running? If you have extra money, buy more/better lighting. You are going to flower with LEDs? IMO, if you have to add supplemental heating to your grow room, you would have been way better off getting a HPS rather than LEDs...

 

[canibanol cannonball]

doesnt fire eat up oxygen...im a little confused

 

[CoolAsAFan]

does burning a candle really produce co2? interesting, does anyone know how? sure fire "eats" oxygen, certainly thats not the methodology of increasing ambient co2? please enlighten me

 

[SherwoodForest]

I thought burning a fire made carbon MONoxide not DIoxide.

 

[Six]

I thought burning a fire made carbon MONoxide not DIoxide.

Hmmm...good point...never thought of that...guess thats why they call it dope...:doh:

 

[purplephazes]

I thought burning a fire made carbon MONoxide not DIoxide.

you are not from the same country as me Head down under !! ok ! Peace ! ooohh you could even get some Co2 tanks and release the air from the tanks and then light the candles to burn up all of the Co2 !! just a thought !!

 

[CoolAsAFan]

"Candle wax is just paraffin, a hydrocarbon. As the name implies, a hydrocarbon contains just hydrogen (H) and carbon (C). When candles burn, most of the wax reacts with oxygen (O) in the air to form water vapour (H2O) and carbon dioxide (CO2). Both water vapour and carbon dioxide are gaseous and invisible. Thus when a candle burns, the wax goes into the air. "

"if there is not enough oxygen in the air when it burns, then it is called incomplete combustion. a colourless, odourless, poisonous gas carbon monoxide can be formed, as well as the much more common carbon (soot)"

learn something new everyday , but as THG said, the amounts produced would be minimal and have little to no effect, most likely the latter.

 

[Head_Down_Under]

Hey Crazy I posted much the same thread yesterday before I found yours, so if the topic still interests you you can pick it up again here
http://www.marijuanapassion.com/forum/showthread.php?p=482045#post482045
BTW some comments suggested that there is little CO2 available from a candle. My high school chemistry (albeit rusty as all) says otherwise. Right now I'm doing the numbers and hope to post the results very soon now

The only serious answers I've had so far are to not use candles: the 2 arguments presented so far are:
1. its dangerous and can start fires
2. it won't work/is pointless if you have decent ventiliation

so its not looking good for the candle. I'd hoped to get feedback from DIYers who'd played with CO2 generators but the thread is still young...

 

[purplephazes]

gee i have not seen crazy horse since 03-18-2007 ! peace and good luck head down under ! this may help you ..http://www.marijuanapassion.com/forum/showthread.php?t=42897

 

[StoneyBud]

O.K. And Hick, like the new avitar lol!

Hey Crazy Horse, you look just the same after all this time!

How are ya?

 

[CoolAsAFan]

interesting excerpt from the following: hxxp://www.stubbornmule.net/2009/03/burning-candles/

"Each hour a small candle burns at least 2.5 grams of candlewax (most candles would be worse than this), which contains a little over 2 grams of carbon, producing 7 grams of CO2 emissions. So 40 candles would produce about 280 grams of CO2 each hour. These figures are based on the Hex Jar burn time in this table of candle burn times, which burns 1.5 oz of candlewax in 12 hours. Many others in the list burn at a faster rate."

now whats the conversion for grams co2 emissions to ppm?

 

[Head_Down_Under]

These calculations should settle whether or not the amount of CO2 from a candle is useful for growing. It uses no more than high school chemistry and maths:

My grow cupboard is 0.5m x 0.45m x 1.5m = 0.337m^3 = 337 litre
Formula for candle-wax (typical) is C25H52
Atomic Mass: Oxygen 16g, Hydrogen 1g, Carbon 12g per mole
Molecular Mass: CO2 44g per mole
Equation for burning wax in air: C25H52 + 38O2 -> 25CO2 + 26H20
Volume of 1 mole gas 22.4 litre

Ambient CO2 level 300part per million (ppm)
Ideal CO2 level for growing 1500ppm
amount of CO2 to add to air for ideal growing: 1200ppm

Mass of 1 tealight candle 10g (my estimate)
duration of burn 4 hours (as printed on side of packet)
rate that wax burns: 2.5g/hour
cost of candle 11cent
Assume: all wax is fully burnt to CO2 and water

Wax contains C(25 x 12g) / (C(25 x 12g) + H(52 x 1g)) x 100 = 85% carbon
Therefore when 2.5g wax is burnt, 85% x 2.5g /12g(atomic weight C) = 0.177 mole C is burnt
to produce 0.177 mole of CO2
Volume of 0.177 mole CO2 is 0.177 x 22.4 litre = 3.96 litre CO2

which raises the following volume of air up by 1200ppm: 3.96 x 1000000 / 1200 = 3300 litre

3300/337(Volume of cupboard) gives 9.8 full air changes at 1500ppm per hour, for burning 1 candle. I think thats quite a good rate, but if I need more airflow then the CO2 level will just go down a bit towards but always above ambient.

I hope that clarifies that part (I also hope I didn't do any maths blunders - I am rusty)

Now to the other bit, assuming that I (or any other intrepid builder) can construct a growroom without burning their housesdown, would the candles pose any other problems I may have missed, and has anyone tried this yet to see if it works? I'm trying to connect with any DIY tinkerers who may have experimented with CO2 assisted growing. I can't believe that I'd be the first to try, surely someone has had a go and feels like reporting back - even if to say it didnt do much for the bother?

In terms of excess heat being generated, Hemp_Goddess and others: I plan to use 2 x 55w cfl, and the Red/Blue UFO 660nm growlamp (90w) that just arrived today.
I ran all of the lights for a couple of hours and the temp sat nicely in the high 20s (Celcius) before I've even built the extractor. So assuming that I'm using enough light to grow a few small plants, there won't be a heat problem for me (its cold in the room the grow cupboard is in, its winter now (southern hemisphere)).

My present downer is that the old unknown seeds I've scored have been sitting on damp rockwool for a week now showing no interest in germinating but thats another story

BTW I make no claim at all to being an expert. This will be my very first indoor grow, I'll have heaps of questons to ask, will often be in need of help
and am really pleased to have found this forum
Cheers