Question on light set up in my new room

[Alex@BFR]

What kind of light set up should I have to grow 12 plants at a very good rate? Right now the general consensus i've been given by the community is that (2) 300 watt LED lights will cover it. Looking for any 2nd opinions on that-

grow room set up will be kind of an L-Shape custom built with 6 plants on opposite ends of the L for ease of access to the plants. With a 6in inline exhaust fan with a carbon filter before it and Ona gel at the end. 4in inline intake with another carbon filter before it. A humidifier (it's avg about 22% humidity in the room so I wanna use that to raise it to around 55%). And 1 or 2 fan. Heat will come from an electric baseboard heater.

 

[astronautrob]

Question, why the carbon filter on the intake? To filter the outside air? I'd just throw a stocking or something on the fan to filter it if that's what it's for. Also I wouldn't waste money on a humidifier, I grow at 20ish% RH and they seem to do fine. If it drops I'll throw a bucket of water in there, problem solved.

 

[Alex@BFR]

Yeah smell security is my primary concern, plant quality second. Dual carbon filters with a bit of Ona Gel seems like the most bulletproof scent cover Especially since they aren't too spendy if you get a fan/filter combo kit. Humidifiers aren't too expensive and I wouldn't mind putting it in my room if I end up not needing it. From what i've learned overall though most people like to grow in 50% so i'm just gonna stick with what works for the masses.

 

[Alex@BFR]

What strain are you growing in the 20%?

 

[lawlrus]

Yeah smell security is my primary concern, plant quality second. Dual carbon filters with a bit of Ona Gel seems like the most bulletproof scent cover Especially since they aren't too spendy if you get a fan/filter combo kit. Humidifiers aren't too expensive and I wouldn't mind putting it in my room if I end up not needing it. From what i've learned overall though most people like to grow in 50% so i'm just gonna stick with what works for the masses.

The most bulletproof odor control you can get is a properly installed carbon scrubber and inline fan setup to create negative pressure within the grow space, with the fan pulling from the scrubber and exhausting out with as few bends, twists, and connections as possible. Adding an additional carbon filter and inline fan to the intake will not create a negative pressure environment and will cause smells to leak, which is the opposite of what you want.

So again, in the order of installation, it goes scrubber > inline fan > out of tent. Don't try to over-complicate things, KISS works wonders when growing pot.

 

[Alex@BFR]

I had planned on a 4in inline fan as my intake and a 6in as the exhaust. So your recommending i remove the 4in inline altogether?

 

[lawlrus]

I had planned on a 4in inline fan as my intake and a 6in as the exhaust. So your recommending i remove the 4in inline altogether?

Correct. Assuming it will handle the air exchange you need, one 6" fan and one 6" scrubber. Always go for overkill with ventilation when you can as you can always use a cheap fan speed controller to dial it down as necessary. Not overkill as in extra fans, but overkill as in the amount of air it can move (CFMs)

 

[Alex@BFR]

So what do you recommend I use to draw fresh air into the room with the 4in inline removed from the equation? And i'm glad i posted this and that you replied- will save me the money if not buying the 2nd inline

 

[lawlrus]

So what do you recommend I use to draw fresh air into the room with the 4in inline removed from the equation? And i'm glad i posted this and that you replied- will save me the money if not buying the 2nd inline

The idea of negative pressure relies on an active exhaust and passive intake. You have the active exhaust part down with the inline fan exhausting air out of the tent. The passive intake is just what it sounds, an opening that allows fresh air to enter. This can be a little confusing because essentially, you are using the inline fan in a manner that is reversed from how it is technically intended, as you are pulling air through instead of just pushing air out, if that makes any sense.

The general rule of thumb to create the proper negative pressure environment is that you want twice the surface area of passive intakes that you have for exhaust. This means that in this example, you would want either two 6" passive intakes or three 4" passive intakes for your 6" exhaust fan and scrubber. Again, this is not a hard and fast rule for all setups and these numbers don't always exactly translate, but if you start there and tweak as necessary you will get to a point where you are achieving negative pressure and thus controlling your odor and providing proper air exchange simultaneously.

Hope that helps.

 

[astronautrob]

I've grown multiple strains at roughly 20% RH, I know it's a little lower than you want but I've never had issues so I've never done anything to "correct" it that's just my personal experience though of course. But yea I'd get rid of the 4in intake and carbon filter for sure, save the money. It really does nothing to help with smell if that's your primary concern