How Much Ventilation Do I Need in My Grow Room?

[Yojitoke]

Thanks that will give me a couple more weeks to get the carbon filter and more money for the fans

As I was thinking the above for the exhaust and I was thinking a fan 137m3/hour for intake which is like 20% less and just the small fans inside but might not even need them.. ( think that should cause an air lock? )

Hot air will go out a window and new air from a coldish room. Smell and sound would be an issue as I live in a flat but the fans Ive picked are around 30 db or 35. That's why if I'm doing it, might as well do it first time around than changing everything later.


But Suppose for now the 120mm will do for the exchange of air and worry in a couple of weeks about the rest.


Thanks for the replay tho

 

[Skybound]

What I meant by airlock was a completely sealed room with no in or out, but that was just something to reference off of.

 

[Yojitoke]

Ah right cool, suppose that may not be the best for me anyway still trying to get all the other basics right

 

[KonopCH]

Intake fan 185 m3/h
Exhaust fan 200 m3/h
Room temp. 26-27°C
Growbox temp. 34-36°C
Growbox: 80x80x160 cm

What to do? Why is growbox temp. higher than room?

 

[Skybound]

Lights make heat. If air is not exchanged enough or lights not cooled, heat will build up.

 

[Gaffle]

That temp is taken from just under lights? Is that taken from canopy height? I have just a passive hole with 4in inline (don't know specific air movement stats) and my temps are legit. I am in a basement, room is under my stairs so it's not as small as a grow box, and I had to use a heater during winter.

If it's getting too hot air isn't moving enough. You can always get a larger inline and make it quiet, check my sig. I sit 5 feet from my room and I can't hear a damn thing from my fan.

 

[KonopCH]

Temp is taken from plants tops, under the light, yes. It's also very windy in tent - from vents.

 

[Collect THC]

You need to be able to exchange all the air in the grow room within 5 minutes. usually one 600 watt light requires a 5 inch exhaust fan with a 4 inch intake fan. Always remember when growing weed that you need to maintain a negative pressure in the grow room. More air going out through the carbon filter than coming in through the intake. This is how you master the odour issues. Good filter, negative pressure, sound.

 

[Skybound]

All the variables involved are trivial. Just focus on what is ideal for a given stage of growth. Consider the bare minimum of needed CO2, and what the optimal RH is for the age of the plant, then work the variables to best accommodate the need.

 

[Peteman54]

I am putting together perpetual system. My question is do the veg and bloom rooms have different ventilation requirements? I am wondering If I can forgo carbon filter and cooling since I will be using T-5 lights in veg room.

 

[Skybound]

I also use a 200 watt T5, so I would pay more attention to how many total watts are being consumed to make light than the shape of the bulb. Also, you will need much more ventilation in bloom as your plants will be much larger and deplete available CO2 in the air much quicker, not to mention those same larger plants will create more perspiration and jack up your humidity. Increased ventilation will help a lot with both of those factors. If you have a sealed bloom room, you would then supplement the CO2 and likely rely on a dehumidifier to try to get the RH down, but nothing beats a fresh exchange of air.

 

[williamreive]

Your need to remove the air out of the room every minute and replace it with fresh air to acquire optimal growth in your cannabis.


Sent from my iPhone using 420 Magazine Mobile App

 

[Slick0ne]

I have a question about air flow in cold dry climate. I finished a grow about a month ago right when the temp and humidity dropped and it was a struggle keeping the humidity over 30%.

So what I am wondering is can I lower exhaust air flow and increase co2 with a diy co2 bottle?

That way my humidifier can keep up and I'm wasting less electric on heating the room. Right now our outside temp has been fluctuating from 60*F down to 15*F so it will be a fight to get the temp/humidity/air flow all right for this next grow.

Also my room is 230cubic feet and I typically run my ac infinity t6 at speed 3-4 or 172-209cfm and everything grew great on the last run. I only grow 2 autos and have a 10" oscillating fan to keep the air moving.

 

[Phytoplankton]

I have a question about air flow in cold dry climate. I finished a grow about a month ago right when the temp and humidity dropped and it was a struggle keeping the humidity over 30%.

So what I am wondering is can I lower exhaust air flow and increase co2 with a diy co2 bottle?

That way my humidifier can keep up and I'm wasting less electric on heating the room. Right now our outside temp has been fluctuating from 60*F down to 15*F so it will be a fight to get the temp/humidity/air flow all right for this next grow.

Also my room is 230cubic feet and I typically run my ac infinity t6 at speed 3-4 or 172-209cfm and everything grew great on the last run. I only grow 2 autos and have a 10" oscillating fan to keep the air moving.

Welcome to the forum, This is a really old thread, not too sure how many of the participants are still around. You might want to start a new thread on the “frequently asked questions” or “how to grow marijuana” forums.

BTW, without really sealing the grow space CO2 won’t get you anything. You could try just using the oscillating fan to move air, and see what it does to the humidity/heat. Use the vents to try and get the humidity where you want it. But, start a new thread, you’ll probably get a lot of good ideas/advice.

 

[Slick0ne]

Welcome to the forum, This is a really old thread, not too sure how many of the participants are still around. You might want to start a new thread on the “frequently asked questions” or “how to grow marijuana” forums.

BTW, without really sealing the grow space CO2 won’t get you anything. You could try just using the oscillating fan to move air, and see what it does to the humidity/heat. Use the vents to try and get the humidity where you want it. But, start a new thread, you’ll probably get a lot of good ideas/advice.

Thank you for the reply. I will try it in the FAQ and see what happens.