First Grow - DIY Grow Box Help

Hello All ! I’ve been reading forums for months and I’ve finally decided to start my grow journey. I decided to build my own grow space in my garage. This is the first thing I’ve ever built and I must say I’ve found it rather peaceful to do. I still have a long ways to go, but I wanted to start this thread to document my journey.

Grow Space : Approx. 4x3x6
Seeds: AK 48 Feminized By Nirvana
Light : VivoSun 400w MH/HPS
Soil: Fox Farm Happy Frog / Ocean Forest
Nutrients: Emerald Harvest 3 part

This is where I am thus far and will continue to post as I progress.

I found this small 6 pack of air vents and I’m wonder if I can use these as a sort of passive intake set up or do I need and actually intake fan.

All suggestestions will be greatly appreciated. Thanks in advance


a 400w HID will cover 6-8 sq ft,
to fill a 3x4 area with wall to wall light u need 600w HID.!

passive intake is fine, just need a light trap in the vent system.

i did the same,
my light traps r in the walls/floor/ceiling of the grow chambers…


thank you for replying.

How to I create light traps in these small vents ?

if the room can be kept dark during flower u don’t need light traps.

otherwise, use 6" insulated ducting, 4-6 feet on each intake with a little curve in the ducting.!


Do you think I can successfully grow 3-4 plants in this space with the 400w MH/HPS setup ?

a 3x4 area can flower 1-50 plants depending on your grow method,
it’d take 2x 400w HID lights to fill the 3x4 space with flower light.
one 600w HPS would do the job also.

use your 400 to grow 2 plants in half of the grow space, a 2x3 area of it.!!

save up and get some HLG Quantum Boards to add to the 400 HID,
then one day replace the 400 with more QB’s.!

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Update progress on grow box build. I’m ordering a inline exhaust fan and will feed the duct through the back of the box.

Should the exhaust fan be directly connected to the light or can it be mounted and the end of the duct ?

I’ve been monitoring temp/humidity and it definitely gets hot in there with the 400W light. I’m hopenthe exhaust fan will cut the down tremendously. Highs have been around 91 degrees :worried:

what r u ordering.?
there is a LOT of junk online.

this is obviously way too high, especially on the floor 4 or 5 feet from the light,
a good inline centrifugal or mixed flow fan will help.!

u have a good 3x4 veg room.!
in flower the light will have to be lower and it will not cover the 3x4 area.

a good fan can be at the end of the duct.
outside the box is ideal, a fan can generate 20-80 watts of heat.!

Sorry for the late reply. Work has been killing me. But what fan do you suggest ? I’m not trying to spend an arm and a leg. :eyes:

Nice! Following…

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Dropped my seeds in water today. Planned on doing it Saturday but things got a little cloudy. :blush:

Let the Journey BEGIN !

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