400 or 600 ?

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Oct 22, 2006
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Sorry guys I know all the info is all on this forum. But I have thought myself into an oblivious state.. I am going to tent off an area for flowering roughly 3ft x 4ft x as tall as I want, hoping to have 6 or 7 plants. Should I get 400w hps or 600w. also not sure if I really need an air cooled hood or not? avg temps in my neck of the woods are low to mid 70's in spring/summer dipping below 60 at night and 30 - 55 in fall/winter. I will be intaking air from outside and exhausting outside in summer and into my living space in winter ( hopefully to keep me warmer )
I bought a 400 and am sorry I didn't get a 600, it could have been a big hassle as I live in a HOT country but it sounds right for you
3'X4'=12 sq ft... more than a 400 will cover efficiently..
I checked my tarot cards.. I see a 600 in your future...:p
Take it from someone who bought a 400w before I bought a 600.....get the 600 now. Not to mention you need it for a space that big. If heat is an issue consider a cool tube or air cooled hood. Jmo
Naah you can do with a 400 watter..:eek: ..Just kidding, you need the 600w without a doubt. They produce some heat, so I would get a cool tube and pipe it so that the heated air can be modified to what serves you best. You probably will have to experiment with it a bit to find the best setup. I say get a cool tube as opposed to a vented hood because I have both and have found that unless you get the MagnumXXXL hood the light footprint is too small and has to be backed up to reach the edges of the grow, which weakens the light intensity to the plants. The cool tube eliminates the footprint. You could do a naked vertically hung bulb if you are experienced, but heat control will be a challenge to master.:)
gotta go w/ the 600 watt. Me goilz love the lumens! :aok:

my first grow indoor was a 4x4x8 with a 1000 watt...
rule of thumb is a min of 3000 lumens per sq ft for vegging and a min of 5000 lumens per sq ft for flowering. You have 12 sq ft, so you want at least 60,000 lumens. The best a 400 is going to put out is about 50,000 lumens. A 600w HPS will put out 80,000-90,000 lumens. Go with the 600W. I would get an air cooled hood. It really doesn't matter how moderate your temps are, you are going to have to cool your light. What are your ventilation plans? Remember thaqt ventilation is for more than heat control--plants need a continual supply of fresh air all the time the lights are on for ;proper photosynthesis.
thanks all I guess it's a 600. THG my plans are to vent outside air into the space, maybe passive or fan, not sure. And under your advise I will be getting the cool tube, so just sucking air out through the cool tube and venting it outside or to another room should do the trick? Is it easy to hook the fan up to the tube and what type of fan and duct supplies should I be looking for. I wanna have the handy man come and drill my vent holes before I set up anything else. I would do it myself but afraid I would crack my stucco walls.

would the Digital Greenhouse 600 watt HPS Grow Light $199
on HTG be a good one and upgrade to cool tube or do you guys know other ones I should look at. Much appreciated
260 bucks shipped to your door. 600w digi ballast and air cooled hood.

Go to eBay and look up item number 170679564894
This is the type of fan I wld suggest. They are called inline fans. I hve a 6 inch that does around 450 cfm.

cool, if I get one of those fans and suck the air through the cool tube will a passive intake work out ok or do I still need a fan to push air in? also shall I assume that the cool tube is fitted for 6" duct
like this-fit 6" duct from fan or whatever.

Passive if using a fan to suck the air....it'll suck air in through the passive inlets and then be drawn through the lights and out.

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