Stealth Attic Grow Tunnel 400w CMH (X3)

Here's what I've been working on for a while now. I've been working on a shoe string budget, so I don't have all the fancy stuff yet, but this will get me going.

The flower room below is 4' wide and 6' long, it soon will have the floors painted white and the end of the reflectors covered with mylar. The whole end wall is easily removable for access.



Here is a shot from the other end of the tunnel. The square hole in the floor is the main access door (2'x2'). Eventually there will be some enclosed veg areas in the back corners.



Here is the window unit a/c and heater. Below it is the mailbox that will contain the ballasts. (barely) There will eventually be a 6" hole in the wall at the top which will re-circulate air being pulled from the far end of the reflector.



A picture from the other side of the access hatch looking into the tunnel.



Here is what it looks like from the outside. I have the insulation to cover it and will soon be covered. The back part is covered with r-30 insulation already as you can see in the distance. This thing barely fits in the attic, an inch of clearance. I've also decided to make that 4" hole a 6" hole to make sure I have enough airflow through the tunnel.



I just had to tell someone about this thing, I'm glad I have a place like this to come to. My gf thinks I sure do spend a lot of time on the internet.

I have 2 large KC 36's being transplanted now and will have them scrogged out in there under one light and flowered. Finances only permit one light for now, but next round will have all 1200 watts cranked up. They are being transplanted into an all perlite hempy trough (under the bed storage tote) and scrogged out onto a 2'x3'10" screen. Dutchmaster Advanced Grow and Bloom with potash+ and also some cal/mag for nutes. Expect a grow log in the hydro section in a few days.

edit;its in the grow diary section, link to it is a few posts down

I will have periodic updates when significant changes are made to the grow room.

lookin good SAM -

Dont let those cats eat your hotdogs!

I've got a great seat for this one You're going to love the crystal production of those CMH bulbs!

Hi Sam,
Very interesting. I love the grow tunnel concept and remember a dude named Agent Smith who did several tutorials on them. That reflective material is sure smooth and almost mirror-like. I hope it works good. That'll be amazing once you get all three lights in there.
Cheers,
ET

I had fun with those mylar panels before they were installed. I was reflecting the sun into my garage with them and wow was it bright in there. No light bulb could ever compare to that.

Sam the Caveman said:

I had fun with those mylar panels before they were installed. I was reflecting the sun into my garage with them and wow was it bright in there. No light bulb could ever compare that.

Click to expand...

Hi Sam,
Too bad you couldn't have left them that way. A solar grow! lol

What's the backing on those panels. Looked like they bent smoothly for the top. Thin foam or what?
ET

Hey Sam, your grow tunnel is awesome!! Its going to be a great space for you, seems like you could get a lot done in there!!! Keep us updated! Check the grow diary forum as well!!

mailbox ballasts! That's how I built mine -- cheapest metal boxes at the store. Just one 400W CMH/HPS ballast put out enough heat, though, that I wouldn't put two in the same mailbox without better ventilation.

Looks nice for a shoe string budget -- good job!

Eviltwin; The curved reflector is made from commercial fluorescent light fixture light dispersion covers. They are clear plastic cover that the light shines through. They can be found at home depot or lowes and some flex more than others. I just glued mylar with spray adhesive to the covers once they were mounted in place. Some of those covers are very brittle and too much pressure from a screw head will crumble them to pieces.

bob; your right, the grow diary would probably be better found on the Grow Diary section vs. the Hydro section. There are a lot of grow diaries in the hydro section, I guess the hydro section should mainly focus on the hydroponic part of growing and not a diary of blooming plants using hydro.

boroboro; you might could see in one of the pictures where I had a computer fan mounted to the end of the mailbox, but as soon as I hooked a power supply to it the motor fried. 500 mah at 12v might have been too much juice for it, its a 12v fan though. I'm going to put a cpu case blower fan on there though for ventilation once I get the other 2 ballasts in there.

Sam, wow man I love it! The mailbox ballast is freaking great! I can't wait to see what happens. Good luck bro.

"I just had to tell someone about this thing, I'm glad I have a place like this to come to. My gf thinks I sure do spend a lot of time on the internet."


I was just thinking last night about how ICMAG is such good place for people to share their passion of growing cannabis: because they can do it without the worry of lose-lip syndrome. Just keep it between us here on ICMAG and on a need-to-know basis elsewhere.

Looks like the perfect little space. Looking forward to your grow log!

I got the ducts in place and turned my stanley blower fan into an inline duct fan using a shoebox and some duct tape, ghetto, I know.


When I get some money, I'm getting an S&P TD150 and some metal ducts ran to the intake on my house a/c.

Edit; Grow Diary here http://www.icmag.com/ic/showthread.php?t=158181

Nice work. How is your garbage can grow going? Interesting to see someone go with multiple 400cmh. I have a similar plan using 3cmh that I may be putting into the works later down the road. Ya got a stalker now....What do you think it can pull for a yield?

Well, the trash can still has root mass and stem nubs. It needs cleaning out, I yielded 3 ozs off that grow. I don't have clones quite ready for it yet, but I'll start a new thread when they get planted.

I guy named Agent-Smith got a 1.34 gpw with his grow tunnel using NFT, sog, 6-9" clones in 2" net pots, so I think the grow tunnel has great potential. As far as cmh yield compared to an hps, I think it is about the same except the quality of the cmh buds is better.

The first grow, I'm hoping for at least 0.5 gpw, so around 8 ounces or so, we'll see.

Looking great so far Sam! I know I was kinda non-existant while you were building and all but I am back now finally and I can help with anything you need. I can't wait to see you get that baby filled up. My first grow tunnel used a 400W CMH bulb and it worked great! Good luck and I can't wait

So are you going to attach the scrog net to the under bed totes? I'm hoping these are the totes with wheels on them so you can just pull it out for top access?

Hey junior grower, it doesn't have wheels on it but you can see the screen on it in this grow diary http://www.icmag.com/ic/showthread.php?t=158181

Ah nice and easy to work on, beautiful use of what is a normally useless and dead space.

The walls are 28" tall and the reflector is ~12" tall. The center of the bulb is 3" above the top of the wall and 31" from the floor.