Grow Room Co2 WHAT TO BUY

[Builder0101]

Can anyone tell me what a good set up is. I need a tank, a regulator, a controller (which I assume will accept a line from the regulator and then distribute the Co2) and a rain tube. I think that is right. I think 400 bucks will buy it all. Don't know what brand controller or any of that. Any help is appreciated.

 

[Mañ'O'Green]

Before we talk about that lets see if it is worth the investment. Before you can sucessfully take advantage of increased CO² all other environmental inputs must be maxed out. Light needs to be 60 DLI in 18 hours that is ~1000 PPFD full spectrum light. Photos in 12 hours ~1450 PPFD and I am not talking about just in the center of the footprint. This creates a lot of heat. The next big hurdle is Temperature and RH in a fully closed space. Here we are talking dedicated Air Conditioning and perhaps additional dehumidifier. You will want to run about 85°F daytime temperatures but even at that no matter what lights you run it will be hot.

Ok you got all of that handled.

How big is the space in cubic feet? I had 192ft³ and a 20# tank lasted 10 days. But my room was not sealed Problem number 1. Too much heat to keep the exhaust system off. Problem number 2

I had an analog Auto Pilot (not made any longer) But I don't think you can get anything for less than $200 that is worth buying. Tank and regulators will be $100 regulator tanks $250+ depending on size. Then there is the hassle of getting gas! $3 per pound. You can rent at gas welding places but that is not cheap.

It really adds up quick price of energy for AC 10amp 120 V x 9 Hours a day = 10.8 Kwh x .30 = 3.24 per day ~ $100 per month just to run the AC.

Anyhow it did not work out for me.

That is not to say it cannot work. I just did not fulfill all of the needs to make it work.

 

[Builder0101]

Before we talk about that lets see if it is worth the investment. Before you can sucessfully take advantage of increased CO² all other environmental inputs must be maxed out. Light needs to be 60 DLI in 18 hours that is ~1000 PPFD full spectrum light. Photos in 12 hours ~1450 PPFD and I am not talking about just in the center of the footprint. This creates a lot of heat. The next big hurdle is Temperature and RH in a fully closed space. Here we are talking dedicated Air Conditioning and perhaps additional dehumidifier. You will want to run about 85°F daytime temperatures but even at that no matter what lights you run it will be hot.

Ok you got all of that handled.

How big is the space in cubic feet? I had 192ft³ and a 20# tank lasted 10 days. But my room was not sealed Problem number 1. Too much heat to keep the exhaust system off. Problem number 2

I had an analog Auto Pilot (not made any longer) But I don't think you can get anything for less than $200 that is worth buying. Tank and regulators will be $100 regulator tanks $250+ depending on size. Then there is the hassle of getting gas! $3 per pound. You can rent at gas welding places but that is not cheap.

It really adds up quick price of energy for AC 10amp 120 V x 9 Hours a day = 10.8 Kwh x .30 = 3.24 per day ~ $100 per month just to run the AC.

Anyhow it did not work out for me.



View attachment 1258775

That is not to say it cannot work. I just did not fulfill all of the needs to make it work.

I run between 85 and 90°.
40w psf atm but that # is going up soon.
TBH my plants grow like wildfire. Perhaps you are right. Perhaps its not worth it. Thanks.

 

[Mañ'O'Green]

Watts per square foot is Bro-science and has nothing to do with the spectrum and PPFD provided to the plant. The DLI (daylight integral) is the number of PPFD presented to the plant over a day. This is the science you want to look at. Cannabis performs best with 28 - 32 DLI as a minimum and will utilize up to 60 DLI but there is a diminishing return on the light over 50 DLI. Unless you are using Co². You want your lights to be full spectrum. That used to mean PAR (photosynthetic active radiation) 400nm to 700nm wave length light but new science is extending that from 350nm to 750nm.

The green in the middle has now been proven to be used by the plant as well as ultra-violet 350nm to 400nm as well as far red 700nm to 750.

Most commercial lights do not include the ultra violet (or enough) but can be added with other sources later. Many lights do now include the far red.

This spectrum is Blue heavy and will be better for the vegetative cycle:

While this leans red heavy and is better for Flowering.

Many lights allow for different spectrum by turning on or off or otherwise adjusting the spectrum.

Reputable Light manufacturers will have this information for you. You may need to do a little math to compare fixtures but here is what I feel you should look for in PPFD.

The PPFD (photosynthetic photon flux density a measure of the photons) foot print can be a shortcut to visually find a good light once the spectrum is correct. They look like this. It gives you the PPFD for a given area at a given height. You are looking for ~1000 PPFD in the center and as much as you can get on the outsides. 1000PPFD will produce about 32 DLI in 18 hours. If running C0² you want up to 1500 PPFD.

Two fixtures with close spectrum and PPFD can have drastic differences (efficiency) in the watts used to produce the same light. This is why watts per square foot is Bro-science.

 

[Bigg Al]

@Mañ'O'Green

How do you feel about the Co2 bags? I've been using them a long time now. And found out how to get more out of them.
Exhale 365. The one you have to start yourself. My temps only get to about 82 in my closet.
Thanks!

 

[Arthur]

My thoughts on CO2.

If there is improvements left to be had in your setup, and style... if your not maxing out runs as it is now... do all that first. Running CO2 is not real cheap... equipment costs, refills etc. And... it comes with it's own sets of issues as well. (Running sealed can really mess with the temps! And... feed mix will need to be changed as well. Faster larger growth means nute use and cost rise too.)

Bags... I suppose if your not extracting constantly, the small additional amount would help some. Again, bigger gains can be gotten thru getting the rest of the setup dialed in.

For a personal grow, I just don't see an advantage... I can get the same weight increase by jumping 1 tent size (provided I'm packed already) and running 1 more plant... much less costly.

Growing for market, that might be a different story

 

[Bigg Al]

My thoughts on CO2.

If there is improvements left to be had in your setup, and style... if your not maxing out runs as it is now... do all that first. Running CO2 is not real cheap... equipment costs, refills etc. And... it comes with it's own sets of issues as well. (Running sealed can really mess with the temps! And... feed mix will need to be changed as well. Faster larger growth means nute use and cost rise too.)

Bags... I suppose if your not extracting constantly, the small additional amount would help some. Again, bigger gains can be gotten thru getting the rest of the setup dialed in.

For a personal grow, I just don't see an advantage... I can get the same weight increase by jumping 1 tent size (provided I'm packed already) and running 1 more plant... much less costly.

Growing for market, that might be a different story

Well it's not legal here and now boss lady only wants a small grow now meaning 3 plants, I can maybe get a way with4 but the Co2 helps my small grow closet. Every 6 months I get a new bag. It dont have to be seal either.

 

[Arthur]

I had a boss lady once, that is a big added factor... limiting plant #s definitely means I'm growing much bigger plants. CO2 will do that. Might also stay away from lower yielding strains like GSC crosses.

 

[Builder0101]

I grow big beautiful plants. The more I think about it the more I think it is not necessary. Everything is dialed in. Faster plants are more work and I barely have time to care for them properly now.

 

[WildBill]

Mañ'O'Green

I was gifted a bottle, regulator and controller. I run the house temps around 66*F in the winter. Given the temps of the house and what the temps will be in the tent with venting off, I think I can maintain 80-85*F. With winter, I know I'll have to get a humidifier for veg.
I really want to use CO2 with my current room, but I really don't want to try in mid-to late flower. Would using CO2 in veg seem worthwhile to give the girls a bit of a boost before going into flower?
With not having a package A/C in the room, I don't know if I can maintain proper VPD. I guess once temps stabilize, I can tweak the VPD a little bit with the humidifier.
That raises another question. With the tent and room being enclosed, can I expect the humidity levels to increase with watering and plant transpiration? Naturally, I'd expect the transpiration impact to be minimal early in the grow with small plants.

I'll clean up my tent today, turn on the lights, move my exhaust fan in the tent, block off the exhaust and intake vents to the room and turn on the circ fans. That'll give me a starting point for temps.

Does the target range of VPD remain the same using CO2?

I still need to calculate my DLI with the lights I have.