CFM exhaust confusion, what?

[DiscoBiscuit]

Plants only use oxygen at the roots. Everything above ground breaths CO2. You might have 250 to 300ppm CO2 in your air depending on sea level. If you don't get fresh, CO2 laden air circulated several times a minute, you'll starve your plants. You could also consider a CO2 system but you'd pay a lot and have to learn a lot to use it.

 

[FreezerBoy]

during the day when the lights on we would be able to open up the closet and let sum hot air out

Consider running lamps at night.

 

[baet]

freezerboy-i hear people running at night. why is that?

 

[Jnugg]

freezerboy-i hear people running at night. why is that?

Common sense...it's cooler at night then it is in the day...outdoor temps DO influence the air temps indoors.

Another reason alot of growers have their lights running at night is because the meter maid won't come by to check the meter and see it spinning mad fast as they cehck the meters during the day time.

Also in some areas the power companies offer electricity at a cheaper rate at night or what is considered "off hours".

 

[baet]

jnugg-good point. i guess because its going to be coldddd outside for now on, i never considered outside temps. if it was a summer grow id be thinkign straight. also saving money on off hours seems good

 

[BLUNToPOTomuss]

Dr. C-

Disco is money with that tidbit! Its not the fresh o2 that we want, its the fresh co2 that you are moving into the cab.

Its an amazing thing to watch them sucking up that co2!!

I run my lights at night because I work days. Plain and simple, Its the only time i have to get in and water them when needed.

 

[Guest]

But I am still unclear as to what is really needed for respiration for our flora. I just do not see them breathing that much air in that amount of time. Let's say we had one cubic meter of grow space. I know in twenty seconds (three exchanges per minute), there is no way I could even exchange one cubic meter of air in my longs, much less process it. I do not think that however many plants I was able to realistically stuff in that cubic meter, they would be able exchange that amount of air in twenty seconds.

Please pardon all ramblings, musings, and misconceptions on my part.

Dr. Conjuror

Hi Dr,

It is not so much about the plants using all of that fresh air in the given time (in your example 20 seconds), but the availability of the fresh air. Plants require both co2 and oxygen from the atmosphere, without them or in limited amounts growth stops and plants die. Although it may be a bit excessive in terms of "enough air" but exchanging the more than required for plant functions due to the need for one to manage heat will not pose any problems imo other than a good healthy supply of fresh air. In nature, there are many wind patterns hard to see with the naked eye, but surely the air is exchanging at a staggering rate in the outdoors in nature. There are no confined spaces to become clogged with stale air from living plants in a smaller closed environment without adequate airflow.

Keep in mind adequate airflow for plants and managing heat is different, as you noted above you clearly understood. On this same thought, keep in mind that ambient temps for people are different and indoor climates are different from place to place. What works for someone in one region does not always work for another.

What is optimal airflow for our flora? This question seems to want to take me in a million different ways to answer, but to keep things short I would have to say unlimited airflow would be optimal, so the plant can take and give what it wants/needs without stress or hesitation from a lack there of. Optimal is a very hard thing to judge imo without first testing multiple factors for noticeable differences within a controlled set. Not all of the genes within this "flora" loved so much by many of us act the same and have acclimated to many different climates and altitudes. Results for what is optimal will vary from place to place, genome to genome imo.

One more side thought if I may. Your reference to a single cubic foot space being exchanged every 20 seconds, and how it would be impossible for yourself to exchange all the air within your lungs. Think about if that airflow was limited, and there was not adequate airflow and how that would affect your life and living. The limited amount of available fresh air would cause you stress just like your flora, and potentially could cause you to die if restricted to dire amounts.

Now think back to not being able to take in all the fresh air in that same space because it is being exchanged at a higher pace (every 20 seconds).

I hope some of these words help clear anything up.

 

[Dr. Conjuror]

Disco - Thanks. The reason I am asking about this is my planned cab in its final destination will need to be pretty stealthy. I will already need about 500cfm of fan for the light cooling portion and I am trying to keep the second fan below a certain size because this will be a selff-contained cab and I will be limited to the amount of air circulation going on around it.

And I agree carbon is the way to go, but I am going to get everything else dialed in before going there.

BLUNToPOTomuss - Thanks. CO2 in the future will be supplemented.


MSG - Thanks for the extended reply. I used the example of a cubic meter of space because i can think of about the maximum number of plants that can be in there and how much air I think they could process in a short period of time. My incoming air is for all practical purposes fresh air. I may just end up buying a CO2 meter or a controller where i can monitor the levels before I can actually implement supplemental CO2, and that way i can do some experiments on exchange rates or simply see that i am not having a huge CO2 ppm drop from "ambient" levels.


Dr. Conjuror