Slackin on co2

Hey all I get the 20 lb tanks of co2 and they run out every 4 days. I'm pretty good at keeping up with it but every once and a whole there is a day or 2 they stay empty and it goes down to about 300-400 ppm is that going to affect it that much?

I think 300-400 ppm is natural everyday air. Don't quote me, but my selective memory says that i've read that before lol. Are you asking if the fluctuation of ppm will effect your plants like a light leak? Idk. Good luck , bump, I'm curious also.

Exactly I'm wondering if like a light leak will it affect my density/weight if I miss a few days of co2 during the flowering period

Like if I had 65 days of flower and missed like10 without co2 what would be the outcome of that would I have 1/6 the bud or does it not matter that much

as long as its not dipping below ambient levels you will be fine. co2 will not increase your harvest by 6 times, so thats a little dramatic of an estimate anyway.


how big of a room are you running to go through a 20lb tank in 4 days?

Big enough u know, it seems to effect density more I have seen and ripening a little faster but I can't determine if that is a factor in the ripening I will know after a few more tests

I do 100lb tank every 14-16 days in a 9.5' x 12' room with approx 20-30 plants at all times. There's usually 24-48 hrs it runs empty until I fill it back up & I haven't noticed any stress. I do drop the temps though when the co2 is out. 83 degrees with & 75 with out. I haven't done any experiments on if dropping temps help or not I just know it doesn't hurt & helps me sleep at night knowing there not cooking.

plants use CO2 in photosynthesis. there are many variables besides CO2 enrichment to crank up the process. assuming all the factors are ideal a little drop in ppm will not have much effect.

Remi1 said:

I do 100lb tank every 14-16 days in a 9.5' x 12' room with approx 20-30 plants at all times. There's usually 24-48 hrs it runs empty until I fill it back up & I haven't noticed any stress. I do drop the temps though when the co2 is out. 83 degrees with & 75 with out. I haven't done any experiments on if dropping temps help or not I just know it doesn't hurt & helps me sleep at night knowing there not cooking.

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100 pound tank every 2 weeks, lol??? you're using wayyy too much. i should say wasting. for the size of your room, 20 lbs. should last you a good month. are you using a controller? i think you should re-read the instructions, your settings are off....

Silky Shagsalot said:

100 pound tank every 2 weeks, lol??? you're using wayyy too much. i should say wasting. for the size of your room, 20 lbs. should last you a good month. are you using a controller? i think you should re-read the instructions, your settings are off....

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was about to say the same thing, a 20lb tank at 1200 ppms last me a month and a half, at 1500 I get a month.

Sorry typo, 50lb tank. I do have the auto pilot controller with fuzzy logic keeping the co2 between 1200-1300ppm constant while the lights are on. I live in a desert and have to use a 12,000 btu RECIRCULATING a/c but still loose minimal co2 from that. All walls, windows, vents, lights, ducts, gaps, leaks are sealed up.

I'm curious you both said a 20lb tank last a month or more but didn't give your set up, size of room, plant count, controller, Please let us know.

my room is about 8' x 10', and i usually run 6 plants/trees, lol. i don't have a controller. what i do is turn my co2 on for about an hour at lights on. then i plug the regulator into a repeat cycle timer. off for 10 min. on for 4 minutes. keeps me a bit over 1000 ppm. sealed room.

10x 10 room, 3 1000 watt lights, 24,000 btu ductless a/c. sentinel c02 controller,40 plants

^^^ooh, i love my sentinel equipment. reliable and nice price.^^^

You guys use a ton of co2 lol. I run a 20 lb tank in 4x8x7 foot tents and one tank last little over a month so 2 tanks per grow ppm kept at 1500 ppm during lights on with 4 air exchanges during that lights on time.

^^^nah, not a ton at all. 20 lbs. about a month...^^^

chuck estevez said:

10x 10 room, 3 1000 watt lights, 24,000 btu ductless a/c. sentinel c02 controller,40 plants

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hmmmm....... similar. I wonder if the window a/c is taking out more than I thought. Nothing I can do about it unless I get a mini split I guess. I pay $35 every 2 weeks or so to fill it up 1 block from the house so it's not killing me but something to look into.

Or is it the fuzzy logic? Chuck does that sentinel do fuzzy logic? I was always told fuzzy logic was more precise at keeping a set number ie: 1250ppm. Maybe it's using more co2 to keep that level.

Remi1 said:

hmmmm....... similar. I wonder if the window a/c is taking out more than I thought. Nothing I can do about it unless I get a mini split I guess. I pay $35 every 2 weeks or so to fill it up 1 block from the house so it's not killing me but something to look into.

Or is it the fuzzy logic? Chuck does that sentinel do fuzzy logic? I was always told fuzzy logic was more precise at keeping a set number ie: 1250ppm. Maybe it's using more co2 to keep that level.

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yes, when running a bottle, you run it on fuzzy. I bet your a/c is killing you. I pay $15 every month or so for a refill.

ok, so I ran out of co2 last week & thought I would see what would happen If I didn't refill for little longer since I never had a monitor in the room until adding the co2.
I dropped the daytime temp to 73.
rh stayed the same
co2 is 348ppm - 582ppm. It averages around 400-450ppm. When I go in room it jumps above 500.

Now this is a "sealed" room so I thought. The only place co2 can be coming in is from the a/c, but damn I didnt realize that much?

Also something else I noticed....with the temp drop All the plants frosted up big time & the purples & blues & yellows & reds & colors just came alive.

So I think I'm gonna try to find a happy medium between 83degrees/1250ppm ...... & 73degrees/450ppm.

Has anyone else noticed the quality change with vs with out co2??? or at least the looks

P.s. sorry op not trying to hijack thread, just getting good response on the subject already here.

i posted this already but Co2 is a waste unless your room runs hot then the co2 will allow your plants to take more heat and still thrive but as far as adding yield, waste of money there are a lot of other technics that you can do for free and get better results and yield then wasting money on co2. i have ran co2 in greenhouses and indoor i also ran co2 from a bottle and i have ran co2 with a co2 generator in a sealed room and in a perfect environment. and its a waste. just my opinion from actual experience and not from the internet.​

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