Grow Closet 400 Watt HPS, Cool Tube, DIY Cardboard Light Trap Intake.

Greetings,
Be gentle as this is my first build. I've been reading as much as possible on here about proper ventilation and light proofing. My chosen location is a closet (2' deep x 3'8" wide x 7' tall) with an "accordian" door not able to be used for light/air (think ventilation) proofing. Therefore I decided to contruct an inner door using Reflectix bubble wrap insulation. The "door" is nothing but a roll of this material with velco strips running down each side (see pictures below). Needing air intake I decided to utilize the already existing 1" gap at the bottom of the door. I used cardboard to build an long "s-shaped" light trap that allows air to flow (it seems) and keeps light out. (see diagram and picture below).

Hardware
CAN FAN 4" HO - 178 CFM Centrifugal Fan (mounted outside closet)
400 Watt HPS - 55,000 lumen HPS bulb (ballast mounted outside closet)
6" Cool Tube w/ small reflector
(May use a carbon filter in the future)

Light Problem
All in all this setup seems very light proof. However, when inside and sealed I can in fact see a faint glow through the reflectix itself. It's not enough to see anything inside, but I'd rather be safe. I believe my solution will be to put a curtain of light proof drapery lining (50% polyester 50% cotton) material in front of the entire reflectix wall/door. This should block all remaining light without a problem.

Airflow
I really have no way to properly test what the actual CFM (fan is rated at 178 CFM) of air flowing through the closet is. If i place a candle on the floor the air coming through the light trap (the length of the door) will easily blow the candle out. You can hear and feel the suction if you place your hand near the exhaust and you can feel the air blowing on your feet. It SEEMS as if it is venting well. If you look at my diagram I intend on hooking the exhaust to one end of the cool tube and leaving the other end open. I know that a 400 watt light will produce a lot of heat, so I am hoping to remove most of that heat using the coot tube itself as the main exhaust.

I welcome all comment/thoughts! I know that this is a small space, but I've seen posts on here with similar setups in cabinets and tents.

Thanks for reading!


-Keenan


[Diagram]


[Outside View - Open]


[Outside View - Closed]


[Outside View - Open (DIY Cardboard Light Trap)]


[Inside View - Top Exhaust Vent]

My 400 Watt HPS arrived, but I just finished getting everything setup so I haven't had time to see how warm it gets...

Getting closer though.

(Took the picture while it was warming up so it wouldn't be too bright... that's why it looks so dim.)

Looks good

Damn, I wish I could convert a closet right now.

I did that about two years ago, I used blackout cloth, which works excellent for light blockage. I like the S tube for the bottom. Escaping light from the bottom was a hard thing for me to fix. I created a black vinyl skirt on the inside of the door. It was good for awhile, but didn't allow ventilation, and eventually was getting caught on the rug.

what about odor?

I run my closet like this:

filter > fan > cooltube > exhaust
w/
passive intakes on the floor.

its 2' by 4.5' 9'tall.

Im doing 3 big skunk #1 under it.

Im planning on 5-10 plants (5 medium or 10 small) next grow.

looking rather good mate

Seeming as how it's a closet, how will you be ventilating it?

Woops, I commented before everything loaded *reading*

Isnt the light cooling enough to pull air in passivly? or is more air movement needed besides fans? I am growing in 3x6x8 closet with a 600 and a 400w hps and have the doors wide open to deal with the heat but was thinking about getting the cooltubes which would also allow me to go vertical and get the air cooling the lamp. I think your setup looks good, just dont be spillin no water on your cardboard too many times to keep it spiffy looking. Lo_0king good

So how warm does it get in the closet after the lights have been on for a few hours?

A few updates and replies.

Due to my safety concerns I have actually moved the ballast inside the closet and placed it on a cinder block. I really wanted to be able to keep an eye on it, and this seemed much safer than leaving it in my attic near insulation, etc.

Odor control hasn't really been a thought yet. If and when things start to get stinky I will be adding a carbon filter on the intake side of the cooltube. My plan is to attach a 6" duct to the now open end of the cool tube and put the carbon filter near the top of the closet on the ceiling.

I must say that without the cooltube I think temps would be out of control. As it stands it can get a bit warm, but shouldn't be a problem during fall, winter, and spring. This may not be a viable setup in the heat of summer, but we'll see.

It seems like I get about 10 degrees warmer than outside the closet. So, if it's 70 in the room it will be 80 in the closet (after running all day). If heat starts to become more of an issue I was thinking about adding SOME kind of active intake. Also, I am considering trying to move the ballast into the neighboring closet (which currently houses my file server... more than enough room for a ballast as well). My only concern is not wanting to run the ballast on an extension cord at all, as I don't know if this is really a great idea.

Get a 6" "duct booster" fan at home depot for like 25$ and use it for a active intake. If you put a short piece of ducting on it and turn that 90degrees, it will block the light in and out. worked great for me when a passive intake wasnt cutting it.