Grow Box Vents

[ppablo]

Hey everyone. Im a First time grower, so cut me some slack. I build my self a 2'x2.5'x4.5' box. Its not quite finished in the pictures. I still have to put the doors on and paint the inside white.
Anyway, the reason for my post is that I am wondering where i should drill holes for the vents? Also what kind of fans or exhaust should i use for a setup this small? Im only planning on have 2 or 3 plants in here. I will be putting in a 400w HPS light.

http://i240.invalid.com/albums/ff83/snowboarder_pete/7937d237.jpg
http://i240.invalid.com/albums/ff83/snowboarder_pete/e65106eb.jpg

 

[captaindank]

lots of options! just keep the idea that you want your exhaust as high as possible as i imagine this is your sole method for removing heat. Is noise an issue? If not i'd use a 4" HO Fan out the top and just drill holes at the bottom and use 90 degree pvc elbows pointed down and on the inside to keep out the light. if those would be in the way for your containers there are other options. those pvcs will help later if you choose to filter incoming air to keep out pests. Balls to the wall you'd have a 6" HO dumping hard, either get that heat out of the surrounding room if possible.

oh and this way you can get away with a bat wing on the inside. Later if you wanna co2, you shouldn't invest more than a co2 boost bucket, and at that point you would have to air cool your light and seal the room up. issuer arise after this so i recommend just passive air flow in a set up that size. peace! :icon_cookie:

 

[jakew215]

if it were i, i would keep it simple. get a hood, duct it to the wall leaving one end open and at the wall end get a big fan SUCKING hot air from the room through the light and out the wall, then have a passive vent at the very bottom of the box pulling cold air in (negative pressure unsealed box)

this is simple and effective and how my friends have done it for years.

many cons though...

cant use CO2.

bugs can get in.

room outside of the box will start to get warmer.

that 400 will put out a lot of heat in that little box.

 

[ppablo]

Do you think I should maybe use a 250w hps instead. I haven't bought the light yet. Heat was the only issue I was worried about.

 

[jakew215]

where will the box be? like the ambient temp around the box and stuff. if you can keep the room around it pretty cool that will help a lot. i would get the 400w. if you vent the hood like a said it shouldnt get too warm, but the room around it will start to creep up but if that room stays cool then you can keep sucking that cool air in and just keep a constant exchange going.

i think this setup will be bomb my friend, do it. keep us posted.

 

[ppablo]

OK so, new updates.
I finished the box up I covered it in white poly, and put in a 250w metal halide bulb.I have a HPS bulb as well but i will not use it till its time for flowering. I'm not sure on what the strain is, but my friend brought back some seeds from BC and he gave me a few of them.
http://i240.invalid.com/albums/ff83/snowboarder_pete/486d0a8f.jpg
http://i240.invalid.com/albums/ff83/snowboarder_pete/0f1f7fa9.jpg
http://i240.invalid.com/albums/ff83/snowboarder_pete/b7111538.jpg

I also added in some big PC fans to help exhaust out the hot air and so far the temp is staying at a consistent 80-82F

Here are my 2 baby's so far, they are 12 days old from seeds. They are about 1 1/2" tall. I have them under a 250W MH light for 24/0. They are in some "Premium Organic soil". I will start giving them nutes probably within the next week or so.

http://i240.invalid.com/albums/ff83/snowboarder_pete/ca8cdba5.jpg
http://i240.invalid.com/albums/ff83/snowboarder_pete/205a41a0.jpg

Based on the pics, how do you think my plants look? Can you tell what kind of strain it will be yet? Ive seen other journals and their plants are almost double in size by 2 weeks. Mine seem to be getting more bushy rather than growing vertically at all. Anyway I'll keep you all posted and hope that these turn into females. But until then any suggestions and advice are appreciated.