co2 question

[rhinobucket]

got the co2 boost setup
how sealed does my room need to be??
can only get about 80% sealed if i go more it gets to hot
does it still work with the co2 falling over the plant
or does there need to be buildup of co2 in the room for it to work
thanks

[Mr. Clandestine]

You want to eliminate as many leaks as possible to keep the ppm stable when you're using CO2. Extraction fans should be timed so that they don't waste the gases by immediately sucking them out of the room. And don't forget that with abundant CO2 in the air (1000-2000ppm), you can let the temperatures rise slightly higher than you normally would and the plants will be less affected by it. In fact, I think the higher temperatures (in the 90s) actually benefit the plants under these circumstances. CO2 is heavier than air, so it'll naturally fall on top of your plants if the dispenser is located above them. Our houses generally contain 250-400 ppm of CO2 in the air we breathe... if it's possible, try to shoot for about 1500 ppm in your grow room. And if you're limited on how much CO2 you have available, I'd use it more in flowering than in veg.

[LuciferN]

Even in a sealed room you have to change the air to get the oxygen out and let some Co2 build up again, so I think that if you have a leak of about 20% of the air it should be all right. The best way to know is to test it and if it is possible to get a Carbon Dioxide Meter this will tell you if the room is ok.

[grey1223]

You definately need a meter when using Co2. You cannot know what the ppm is without it. You're right the Co2 will fall to plants but most of us have too much air movement in the room to depend on this method. How large is your area? If it's closet sized the Co2 will find it's way to plants, but if it's a average bedroom size you need the entire room to have at least 1000ppm. Hopethis helps.

[rhinobucket]

thanks, i will go pick up a meter
its in a closet, but i shut both doors when its on
i should have asked the question like this
does it need to be like
im running the car to kill myself
or your at a monster truck show

[grey1223]

Running the car to kill yourself. Actually I haven't used the emitter system if that is what you're using. But with a meter I believe you'll be able to use a timer to maintain the ppm's you desire. Just measure how long it takes for your closet Co2 level to drop below 1000ppm. If it takes 2 hours to use up the Co2 then set your timer accordingly. I hope this helps. When I use Co2 I'm fortunate to have a Co2 generator and natural gas in my neighborhood. I'm working on a problem with this crop so I'm not using it this time. If all conditions are not ideal Co2 is a waste IMHO.

[CashandPrizes]

I definitely agree with grey, that if everything else isnt going correctly, leave the co2 out of it.

I thought i had heard that some people do not even use co2 in veg...

is there anything wrong? or are the benefits just not as potent?

[grey1223]

I believe a number of folks don't use Co2 during veg for the same reason I don't--Vegging plants already grow plenty fast, but the real value lies in extra Co2 for the flowering plants as now your'e talking about yield.

[chrisdl805]

I have seen the Co2 Boost at the hydro store and thought it was a cool/cheap way to get some co2. I'm not sure how exactly that it works, but I think its some type of mushroom/yeast mix, that lasts for about 60 days? I'm not sure how you could hook it up to a meter. You might be able to just measure the co2 in the room. Then figure how long it takes to fill up your closet to your desired ppm and how long it stays in for then set a timer accordingly. Still a meter is expensive and the C02 boost is supposed to be an economical way of providing Co2. If you buy a meter you could get a 20lb tank for $140 that you can fill or exchange for about $20 and it will be much more efficient and economical than buying more boost buckets. How much are the replacement buckets? I was lucky and a friend let me use his co2 digital sequencer and a temp/humidistat that turns it off when the fan comes on as to not waste your co2. If not for him I might have got the Boost kit. Let me know what you end up doing I'm curious to find out.

On a side note I have a C02 question. I have read on some Ed rosenthal Q&A's that when using Co2 and you have 60-100 watt/sqft that you can and should be running 1500-2000ppm of co2. I have about 70w/sqft so I was wondering what everyone's thoughts on this are? I know a lot of people here say to match your co2 ppm with your nutrient ppm, but if Ed Rosenthol said it then it has to be correct, right?

Just in case people were sure, this is what you have...right?

[jchap]

how are co2 tablets that you just add to the water ??

[Mr. Clandestine]

On a side note I have a C02 question. I have read on some Ed rosenthal Q&A's that when using Co2 and you have 60-100 watt/sqft that you can and should be running 1500-2000ppm of co2. I have about 70w/sqft so I was wondering what everyone's thoughts on this are? I know a lot of people here say to match your co2 ppm with your nutrient ppm, but if Ed Rosenthol said it then it has to be correct, right?

Here's a paragraph from one of Ed Rosenthal's growbooks:

To find out how much CO2 is needed to bring the growing area to the ideal
2000 PPM, multiply the cubic area of the growing room (length x width x
height) by .002. The total represents the number of square feet of gas
required to reach optimum CO2 range. For instance, a room 13' x 18' x 12'
contains 2808 cubic feet: 2808 x .002 equals 5.6 cubic feet of CO2 required.
The easiest way to supply the gas is to use a CO2 tank. All the equipment
can be built from parts available at a welding suspply store or purchased
totally assembled from many growing supply companies. Usually tanks come in
20 and 50 pound sizes, and can be bought or rented. A tank which holds 50
pounds has a gross weight of 170 pounds when filled.

A grow room of 500 cubic feet requires 1 cubic foot of CO2
A grow room of 1000 cubic feet requires 2 cubic feet of CO2
A grow room of 5000 cubic feet requires 10 cubic feet of CO2
A grow room of 10,000 cubic feet requires 20 cubic feet of CO2


I want to get a tank and emitter system going, but they can be pretty expensive to get set up. Also, like grey1223 stated, if growroom conditions aren't ideal (sealed room and vented on a timed schedule) then much of the CO2 that's produced is wasted before the plants ever have the chance to utilize it. If you're able to keep temperatures in check, then fermentation and methods generators (propane heaters) are a cheaper and still very effective way to go.