400w or 600w for this grow tent?

Hey guys!

I'm about to purchase a tent ( http://bg-support.com/products/en/Grow-boxes/Homebox-L-1-x-1-x-2-m.html ) 100x100x200 in size, but I'm unsure about which light bulb to buy..

Would I potentially get a lot more from a 600w than a 400w, or would it just be a waste of watts in your opinion(s)?? I'm talking about the HPS for flowering here..

As for the vegetative period, how many watts would you recommend, considering that I'm probably not gonna vegg them for that long (3 weeks max). Would 250w be okay, considering the size of the tent? Or should I just go for 400w..


Thank you!

Thats pretty small, I think you can use a 250 in there full time, I think a 400w would be overkill in that space.

i know where you can get that for MUCH cheaper

i have that exact same tent and i use a 400watt and its perfect

exact same size anywayse

I'd try a 400 in a cool tube or coolable reflector, heat would def be a problem so I'd do independent intake and exhaust for the light. remember to exhaust all heat up. convection causes hot air to rise.

look this over and it may help you pick. https://www.rollitup.org/grow-room-design-setup/167842-air-handling-4x4x8-430watt-flower.html

it's about the same size as you tent.

Crownmesire said:

I'd try a 400 in a cool tube or coolable reflector, heat would def be a problem so I'd do independent intake and exhaust for the light. remember to exhaust all heat up. convection causes hot air to rise.

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Thanks, I think i will go for a 400w.. it won't be on for that long anyways, so might as well use one that will max out the growth..

I'm so unsure about these cooltubes and coolable reflector (same as 'coolshade' right?). Why would one pick one over the other?

Plan is to have passive air intake, and active outtake. Would it be enough to let the air blow out through the lamp/or reflector?

I HIGHLY recommend a cool tube if you can afford it. I grow in a 2x4x5 tent with a 400W HPS. Its really hard to keep it cool enough. I need around 450 CFM of exhaust with a DIY cooltube to keep temps down, and its barely enough. And i have to keep my plant about 16 inches away from the light. Which is OK but closer would be better but its too hot. If you can A/C the room the tent is in you'll be ok, but if not your biggest problem in that tent will be heat. I dont see a passive intake system being enough, but it depends on the CFM's of your exhaust i guess.
The biggest advantage of a cool tube is that it will allow you to put your plants MUCH closer to the light without burning them. This is a big advantage. Definitely better than just a coolable hood. Also will come in handy if you want to introduce CO2.