# 400watt 4x4 grow tent DWC grow



## converseking (Mar 13, 2008)

ok im thiking of setting up my first grow room in a 4x4 htg grow text with a 400 watt hps and 2 DWC's 6 plants( each with 20-30 gal res) each for a total of 12 plants. and having a few mum's (witch i will start from seeds) under flo lighting to take cutting's from. 4x4 2bulb flo's but im thinkin about cuttin down to 2x2. would that be a good idea?

i want to use a sog op for this and bulid the DWC's myself (i think i got the idea of how 2 build them but wanna be sure) but not really sure how to go about this. any advice?

is a 400watt hps eough light for a 4x4 grow tent? should i get more light? would DWC be good for sog op? could i grow more then 12 plants useing DWC in 4x4 grow tent? or by useing ebb & flow or something else in this size set up? if so how?

if u hav any experence with this plz help and thanks 

p.s 

add any extra info u think that would be helpful and thanks again


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## LoudBlunts (Mar 13, 2008)

the 400watter should be fine.


have you already purchased the tent?


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## converseking (Mar 14, 2008)

no not yet but i was going to soon. should i go bigger?


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## LoudBlunts (Mar 14, 2008)

i dont think you should get the htg tent!

the tents are priced just as high as other quality tents. secret jardin dark rooms are the shit!


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## Budsworth (Mar 14, 2008)

I wouldnt use the 12 plant set up DWC with seeds.. Use clones if you can. Once you see males and remove them you have a root issue to deal with. You can do it but clones
are the way to go.


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## converseking (Mar 16, 2008)

i dont have any clones so i have to start with seeds what would be wrong with the roots starting from seeds?


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## converseking (Mar 18, 2008)

Budsworth said:


> I wouldnt use the 12 plant set up DWC with seeds.. Use clones if you can. Once you see males and remove them you have a root issue to deal with. You can do it but clones
> are the way to go.


 i was saying that i would use clones but i'll have to start mum's from seeds first. so would that be good for the (2) 6 plant DWC's? and do u think it'll be better if i go with more light like say 1000watt hps?


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## Mr Green Man (Mar 18, 2008)

If you can get a 600HPS, 400 is enough but 600 is better.

I am growing 8 plants DWC in a slitly smaller space than you. 90x70x200cm With a 400HPS, I will be getting a 600 to use in a slitly bigger space next time round. 

I haven't finsihed my first grow yet so I can't tell you how I did, Just that it is going very well. DWC is great.
If you have 4x4 and you are growing from clones, you can probably fit more like 16 maybe more. Try and get two big 2x4 contaniers, remember you will need around 3 to 5gal per plant depending on how long you veg. For a SOG keep the veg time short and have lots of plants.

Here are a couple of links read these before you purches anything. I'm using this system to great effect.

CC Hydro 101 by Earl - Cannabis Culture Forums

DWC, Bubblin' Buckets, What's Needed And How To - Cannabis Culture Forums


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## converseking (Mar 18, 2008)

how well do u think it'll go if i skip he 600 watt hps and jus go for a 1000 with 16 plants? i hear 1000watts is jus right for a 4x4 space. and what do you think about areoponice hydro systems? i was thinking of gettin (2) 8 plants systems instead of the DWC's and puttin them in a 4x4 grow tent as well( they would take up a 3x4 space side by side) im jus not sure if if they'd be worth the extra money but some one told me they where the best and hardest to use of all hydo's. any input on any of this would be a great help.


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## Enigma (Mar 18, 2008)

converseking said:


> ok im thiking of setting up my first grow room in a 4x4 htg grow text with a 400 watt hps and 2 DWC's 6 plants( each with 20-30 gal res) each for a total of 12 plants. and having a few mum's (witch i will start from seeds) under flo lighting to take cutting's from. 4x4 2bulb flo's but im thinkin about cuttin down to 2x2. would that be a good idea?
> 
> i want to use a sog op for this and bulid the DWC's myself (i think i got the idea of how 2 build them but wanna be sure) but not really sure how to go about this. any advice?
> 
> ...


 
If you are using a 4x4 space for all of your plants don't expect to keep mothers in with flowering clones. You will need a seperate space for the mothers to veg.

Hydroponics first time around? 

Nah, go soil.. less of a headache for the first time.. Soil is much more forgiving.

I had a couple of buddies.. well I kinda found out about their grow due to poor security and they let me in on it.. as security.. and we ran the DWC under 1000w MH and HPS in a DWC using 6 plants.. I did better on my own with smaller lights and soil.. first time.

READ READ READ

There is an overabundance of information here and on CannabisCulture.com



converseking said:


> how well do u think it'll go if i skip he 600 watt hps and jus go for a 1000 with 16 plants? i hear 1000watts is jus right for a 4x4 space. and what do you think about areoponice hydro systems? i was thinking of gettin (2) 8 plants systems instead of the DWC's and puttin them in a 4x4 grow tent as well( they would take up a 3x4 space side by side) im jus not sure if if they'd be worth the extra money but some one told me they where the best and hardest to use of all hydo's. any input on any of this would be a great help.


 
1000w; 150,000L = 150L/w
*600w; 95,000 = 158.2L/w
*400w; 55,000 = 137.5L/w

1000w = 37,500L/sq. ft. @ 24" above the canopy
*600w = 42,222.2L/sq. ft. @ 18" above the canopy*
400w = 24,444.4L/sq. ft. @ 18" above the canopy

Don't expect to use all of that 4x4 space.. take it in maybe 6" on each side.. that is your *USABLE* area.

Hydroponics, I think, is out of your league as a first-timer.. aeroponics for sure.. so much to go wrong.. so much to setup.. there is a post on here that a guy spent $3k in equipment and killed his whole crop.. well, several.

I'd go soil first.. feel things out.. soil is more forgiving.

But hey, there might be something I missed along the way.. so read around a bit and see if you can answer your questions.. oh, and go with the Dark Room.. the HTG tents aren't what they are cranked up to be.



Enigma


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## converseking (Mar 19, 2008)

what do u mean? what wrong with them? what makes a dark room so much better? maybe your right about the soil grow but im really in2 hydro and would like to go that way even for my first grow. what did your friends get in dryed product after their first 6 plant DWC grow?


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## Enigma (Mar 19, 2008)

converseking said:


> what do u mean? what wrong with them? what makes a dark room so much better? maybe your right about the soil grow but im really in2 hydro and would like to go that way even for my first grow. what did your friends get in dryed product after their first 6 plant DWC grow?


The first time around was less than an ounce each. That was barely over a *QP* from *6 plants!* It took them a few grows to figure it out.. I grabbed some soil and put them to shame.. I don't remember exact numbers on it.. I'm bad at keeping notes.

Soil is just more forgiving for the first time around.. 1/4 strength nutes maybe once a week and plain tap water maybe once a week depending on soil. I've never worried about pH or PPM or pumps or failures for soil. Just water them, feed them and give them light with a fan.

Oh, and I've never experienced any bugs.. I keep shit clean!

HTG Grow Tent

Dark Room

Dark Room Street


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## southfloridasean (Mar 19, 2008)

IF you want to go hydro do DWC until you get all your ducks in a row for aero. Keep your water level & ph steady with DWC if thats what your starting with & youll be alright but you have to be committed. Soils a nuisance. However, if you got balls & do some intensive reading shoot for aero. Why not.....Thats the only way we will all learn is from trial & error. Shoot for the stars, land on the moon.


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## converseking (Mar 31, 2008)

Nah, go soil.. less of a headache for the first time.. Soil is much more forgiving.

Hydroponics, I think, is out of your league as a first-timer

mayb hydro is out of my league for my first time but i think i can handle it bt i might b wrong we'll c lol i was thinking of going soil first but i'd rather go hydro first and take the risk i think the shorter time for growing and better weed you get from doing hydro will be will worth any headache and if i do mess up and have to start over at least i'll already have some experence on growing hydro instead of just in soil wen i'll still just have to end up trying hydro later and getting that same experence from growing that way later anyway


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## converseking (Mar 31, 2008)

southfloridasean said:


> IF you want to go hydro do DWC until you get all your ducks in a row for aero. Keep your water level & ph steady with DWC if thats what your starting with & youll be alright but you have to be committed. Soils a nuisance. However, if you got balls & do some intensive reading shoot for aero. Why not.....Thats the only way we will all learn is from trial & error. Shoot for the stars, land on the moon.


thanks dude


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## southfloridasean (Mar 31, 2008)

No problem but dont think your going to mess up your only manifesting negative energy. Feel the enjoyment of your harvest even before you pop your 1st seeds. Positive thinking is what its all about.


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## converseking (Apr 2, 2008)

nal dude its all love over here lol i gotta ? if i use a 2x3 set up with about 6 5 gal dwc bukets do you think i should go with a 250 wattt hps or a 400 watt air cooled light? I know heat would be a problem with the 400 in such a small place thats why it would be aircooled. do you think it would be worth it to just get the 400's for the small space and deal with the heat problem as it comes with fan's and what not?


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## southfloridasean (Apr 2, 2008)

Well I would rather see you with the 400 watt lamp. The 250 watt wont give you much light penetration for 6 plants. Youll get popcorn buds. Also youll need an inline fan with a a carbon scrubber to get rid of the heat. You dont want heat to be a problem with the water in the gallon buckets it can make you get root rot.


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## converseking (Apr 2, 2008)

southfloridasean said:


> Well I would rather see you with the 400 watt lamp. The 250 watt wont give you much light penetration for 6 plants. Youll get popcorn buds. Also youll need an inline fan with a a carbon scrubber to get rid of the heat. You dont want heat to be a problem with the water in the gallon buckets it can make you get root rot.


 a inline fan with a carbon scrubber? what is that and where can i get one? and how much would it cost and how would i set it up in a colset?


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## southfloridasean (Apr 2, 2008)

charcoal carbon scrubber OpenDNS
vortex inline fan or soler & palau fan use google


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## southfloridasean (Apr 2, 2008)

oh & you want your intake air to be at the bottom & the exhaust ventilation to be at the top of your grow room. hot air rises to the top so the exhaust fan will eliminate it. Your cool air will be at the bottom so the plants can get clean beneficial air.


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## thecloset (Apr 2, 2008)

i went with 2 dwc 5 gallon buckets in a closet under a 400 watt hps for my first time using general hydroponics nutrients and yeilded around 9 ozs total of some of the nicest ive ever smoked from the two plants.... didnt have any fans running through the light just one small fan on the floor of the closet pointing up at the light. temps were far from ideal, it was the middle of winter so the night time lows were around 58F but the closet was so small that the max temp got up to 108F. all i did was change the reservoirs once a week and i vegged for 3 to 4 weeks before putting it into flower... if i was u i would start out with something similar to what i did: two 5 gallon dwc buckets (home depot paint bucekts work great), and maybe abouta month and a half into it start your mothers in another area. changing the buckets even once a week can be a huge pain in the ass so i can guarentee that trying to change 6 of them once a week will be no fun at all. u could try to spread it out so that u change one of them each day but for ur first grow 6 plants might just be too much to look after... once u get ur first harvest and ur mothers are nice and bushy then u could make a larger dwc or even aero set up with clones that u know are going to be female. i think u might have missed the point that someone was making earlier about starting from seed in a dwc system with multiple plants in it... if one of those plants turns out to be male and u have to pull it out ull never be able to get all of the roots out of the reservoir and ull inevitably be left with dead roots that could cause problems for your other plants.


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## converseking (Apr 3, 2008)

thanks i think you maybe right about gowing with only 2 plants for my first grow. i'll be able to take care of 2 plants way better then trying to look after 6 espcially for my first grow. the only reason i even wanted to go with so many on my first shot was to up my chances of getting a gul becuz it'll be hell if i get both males and have to just start all over. but the 2 would be better so how many sq ft was the closet you growing in? and what nuts did you use from HG? and how did you use them tew out your grow to get the 9oz's? and how tall where your plants b4 you started to flower them? and what strain did you use? i was thinking bout m39 since it folwers so fast. do you think if i use HTG's easycool 8 reflector with the 400 watt hps and a fan in the 2x3' closet for more air movement that that'll controll the heat? srry bt i have alot or ?'s lol just trying to get everything rigth. and thanks for clearing that up about the starting for seeds thing. makes since now


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## converseking (Apr 3, 2008)

southfloridasean said:


> charcoal carbon scrubber OpenDNS
> vortex inline fan or soler & palau fan use google


 ok i'll check that out thanks


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## Enigma (Apr 3, 2008)

converseking said:


> ok i'll check that out thanks


 
If your strapped for cash check my sig...


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## converseking (Apr 3, 2008)

sure thanks


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## converseking (Apr 3, 2008)

this is everthing i was going to get for my 2 5gal DWC buckest grow in a 2x3' closet most from htgsupply.com.

Rockwool / Stonewool 1" Cubes - 45 pack

Champ pH Meter

Sunleaves TDS Essential Calibration Solution 

50 foot by 48 inch roll Mylar - 1 mil

Sunleaves TDS Essential Digital Test Pen 

2 Elite 801 Air Pumps

2 Sunleaves 6" Air Stones

Sunleaves Air Tubing 20ft

Hydroton 2 Liter Bag

TEN PACK - 3" Net Pots 

HTGSupply Ultimate 400w HPS & MH Grow Light
EasyCool 8 Reflector
HTG Supply 400w HPS Bulb
GrowBright 400 watt MH Conversion Bulb
Sunrise Hi-Low Reflector Hangers
Dual Outlet Digital Timer w/ Battery BackUp

FloraNova Bloom & Grow by General Hydroponics - FloraNova 2 Pack
Size: Quarts

2 5 gal buckets with lids

Reusable Tray Insert for Rockwool

Standard White Flat Tray

Mondi Humidity Dome 

what do you guy's think? anything i need to add or wont need?


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## converseking (Apr 6, 2008)

so what do you guys think?


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## Mr Green Man (Apr 7, 2008)

I would go with the 600, it's only going cost like 50 more bucks, that means you only need to produce 1/4oz more weed with it to make a profit. 1000 is probably over kill for that space, unless you want to build a bigger space, remember, you will need somewhere to put your fans, maybe a de/humidifier, even a heater.

It's my first time to, and I'm getting on real good with DWC. There is a lot to it, you will have to read and read and read, Befor you start. but if you have the time I highly recomend it as a way of growing. 

The thing I have found i with hydroponics is that there is more to it, but as long as you are aware of the factors, it's a lot simpler.

As for airo ponics, ment to be even faster, I haven't tryed it yet, if you decided to go this rout, I would recomend getting a back up power supply, for the pumps. If the Ellectric goes off in DWC you have 4 hours befor things go bad, in ario you have like 30 mins. Thats the scaryest thing about it and the only thing that makes me feel uneasy.

Ebb and Flow is ment to be very newbi freindly. but maybe a little more comlicated to home build. 


Top Tip DWC: If you are getting rubbermades for DWC get 1 spare, use this for rez changes, make up your mix in the spare rubbermade, make it compleatly correct, Temp, Level, PH, PPM, and then simply swap the lids around, so your plants are now in the new rez and push it back under the light. For this to work properly you must have no lip or step into your room.


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## Mr Green Man (Apr 7, 2008)

hi, we possed at the same time.

If you have the cash, then go ahead, you can probably make some of that stuff, if you are so inclined, but hey if you don't need to why bother.

Try to use as little rockwool as possible, it doesn't go with DWC to well.
I would spend more money on air pumps, The more air the faster you plants will grow, also stones can clog and pumps can break, I'ts good to have two in each rez so you have a back up. I would have 2x pumps and 4x 6" stones Each rez, and a Submersable pump.
The submersable pump will add more air, but most important, in a few weeks you tanks will be full of roots the pump will insure that water is kept moving.

What sort of water are you using?
Tap water, what quality is it?

Find out before you get nutes beacuse there are specific nutes for poor quality Tapwater. 
You will need some PH down.
I use an Enzym and Silica in my rez. They both keep roots helthy.
I also recomend getting a fish tank thomometer. You need to keep your rez and 19c or 66f, this is very important.

The air pumps maybe cheaper at your local pet shop.


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## converseking (Apr 7, 2008)

Mr Green Man said:


> Try to use as little rockwool as possible, it doesn't go with DWC to well.
> I would spend more money on air pumps, The more air the faster you plants will grow, also stones can clog and pumps can break, I'ts good to have two in each rez so you have a back up. I would have 2x pumps and 4x 6" stones Each rez, and a Submersable pump.
> The submersable pump will add more air, but most important, in a few weeks you tanks will be full of roots the pump will insure that water is kept moving.
> 
> ...


 i've decided to go with (3)5gal DWC buckets for my first grow. that'll prob be better for me. i think that the air pumps( recommended for a 15gal rez) and the 6'' air stones in each bucket should to well. do you think i should go for the bigger air pumps( recommended for 20gal) or stick with the ones i have? i know more air is better but a 20gal air pump seems lik over kill unless i use the one pump for to airstones( one in each rez). thinks for the idea about haveing extra rez's that'll prob save alot of time and keep me fro messing up to bad on changing the water/nut's. what wood you say is better for DWC if not rockwool? i was thinking of using rapid rooter starter plugs myself instead of rockwool for DWC then go for the rockwool wen i start up a ebb&flow. what do you think? 

the submersable pump you speak off yu mean a water pump right? i kno that helps with water movement in the rez but how will it get me more air in the rez? i prob should get a thomometer for each bucket. how important would you say they are to have?

i will be using just normal old tap water unless i decided to buy water but i dont see that happen as i could jus let the tap water sit out for like 3 days or jus use a few drops of ph down on it.


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## converseking (Apr 7, 2008)

Mr Green Man said:


> I would go with the 600, it's only going cost like 50 more bucks, that means you only need to produce 1/4oz more weed with it to make a profit. 1000 is probably over kill for that space, unless you want to build a bigger space, remember, you will need somewhere to put your fans, maybe a de/humidifier, even a heater.
> 
> It's my first time to, and I'm getting on real good with DWC. There is a lot to it, you will have to read and read and read, Befor you start. but if you have the time I highly recomend it as a way of growing.
> 
> ...


 i was thinking of getting a 3.9'x3.9' dark room but not sure i wanna spend the money jus yet. 600 would prob be better but that'll mean more heat so i'll go with the 400 pluse wen i decided to get a bigger ebb&flow system under 1000+ lights the 400 watt with a MH conersion bulb would be good in my veg/mother/clone room and i thenk that 600 watts MH wood be a lil much for a lil-mid size veg area.

yes reading is the key to success  lol. i've read alot from books and the web and i think that i kno jus bout er thing their is to know about each hydro setup the only way i'll learn anymore the i already kno is to start growing myself.their is alot to growing hydro but i think i can handle it i just need 1 or 2 grows under my belt and i'll be good.

im not even thinking of going airo ponice at least not anytime soon i mean it's great for those that do and can handle it but for me it's to much to go wrong maybe i'll try it later on in life( alot later lol)


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## converseking (Apr 7, 2008)

thecloset said:


> i went with 2 dwc 5 gallon buckets in a closet under a 400 watt hps for my first time using general hydroponics nutrients and yeilded around 9 ozs total of some of the nicest ive ever smoked from the two plants.... didnt have any fans running through the light just one small fan on the floor of the closet pointing up at the light. temps were far from ideal, it was the middle of winter so the night time lows were around 58F but the closet was so small that the max temp got up to 108F. all i did was change the reservoirs once a week and i vegged for 3 to 4 weeks before putting it into flower... if i was u i would start out with something similar to what i did: two 5 gallon dwc buckets (home depot paint bucekts work great), and maybe abouta month and a half into it start your mothers in another area. changing the buckets even once a week can be a huge pain in the ass so i can guarentee that trying to change 6 of them once a week will be no fun at all. u could try to spread it out so that u change one of them each day but for ur first grow 6 plants might just be too much to look after... once u get ur first harvest and ur mothers are nice and bushy then u could make a larger dwc or even aero set up with clones that u know are going to be female. i think u might have missed the point that someone was making earlier about starting from seed in a dwc system with multiple plants in it... if one of those plants turns out to be male and u have to pull it out ull never be able to get all of the roots out of the reservoir and ull inevitably be left with dead roots that could cause problems for your other plants.


what size where your plants b4 you started to flower them?


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## converseking (Apr 11, 2008)

southfloridasean said:


> oh & you want your intake air to be at the bottom & the exhaust ventilation to be at the top of your grow room. hot air rises to the top so the exhaust fan will eliminate it. Your cool air will be at the bottom so the plants can get clean beneficial air.


 what if i wanted to use ducting with a 6'' cooled reflector? wouldnt i need the intake fan with the carbon at the top to attach to the reflector? im not sure on how to set up any of this


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## thecloset (Apr 14, 2008)

my plants were only maybe about a foot tall when i started flowering them... they ended up being about 4 feet tall. i would highly recommend getting the extra buckets like mr green man said... it makes a hell of a lot easier to swap the res out. id have to disagree with him on the rockwool tho... i highly recommend using the 1 inch rockwool cubes to start your seedlings in a smaller tray. once roots have come through that, put them into 4 inch rockwool cubes and then put those 4 inch rockwool cubes into round 6 inch net pots that u build into the lids of the buckets. the 4 inch cube will fit snugly into the net pot, meaning that u barely have to use any hydroton. just enough to cover the top of the cube and fit down in the cracks between the cube and the pot. it also makes the whole plant much more stable as moving the lid around a lot when changing the reservoir could cause the plants to fall over if the roots arent well established yet. this might not be too much of a problem as the roots tend to grow rather quickly in a dwc setup.. good luck with everything


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## converseking (Apr 16, 2008)

thanks a ft is just about where i was thinking of flowering to.thats a good idea about the rockwool with the net pots thats jus what i'll end up doing. how much did you get of dry weed from the 4ft plants?


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## Yota (Apr 16, 2008)

Hey, i didnt have time to read every post, but heres my 2 cents. 

I have a 4 X 4 space and used a 400w for a while, probably 3 grows. After that , i wished i had bought a 600w. So my advice is to get at least a 600w for the 4X4 space. After that, id say go for hydro system. Ebb flow systems are easy and dont involve drip tubes that can get clogged. Plus with hydro, u can leave it for a weekend or several days and it wont be an issue. Another tip is to make sure your ventilation is good, and that u have some oscillating fans. If u stick with the nutrient schedule and know how to measure your ph, than you should be fine with hydro. Also, i have had problems with rockwool, and i use coco as a medium. You can look into what medium you prefer, but coco is very good for an ebb flow system because it allows lots of oxygen to get to the roots, and when the water flood the tray, it push's old air out, and new air comes in. Anways, i hope some of that was useful to you


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## thecloset (Apr 16, 2008)

almost 9 ozs from the two plants combined dry weight


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## Yota (Apr 16, 2008)

converseking said:


> what if i wanted to use ducting with a 6'' cooled reflector? wouldnt i need the intake fan with the carbon at the top to attach to the reflector? im not sure on how to set up any of this


no, intake fans should be coming into your garden. You don't really have to have one (do some reading about that). You will need a exit exhaust fan getting rid of the air from your room. You could attach the carbon filter to some ducting to your reflector, and from your reflector out of the garden, yes that would work.


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## Mr Green Man (Apr 17, 2008)

Hi,

Sorry for the slow replie.

Regarding pump, all the aqurum pumps I have seen come with an air line that attches to the exit on the pump, as the water is oumped threw it also sucks air down the line. It's not as good as an air stone but every little helps.

One thing I would say about using bigger buckets is that it is easyer to keep, PPms, PH and Temps stable. 

Good luck with your grow.


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## converseking (Apr 18, 2008)

Yota said:


> no, intake fans should be coming into your garden. You don't really have to have one (do some reading about that). You will need a exit exhaust fan getting rid of the air from your room. You could attach the carbon filter to some ducting to your reflector, and from your reflector out of the garden, yes that would work.


 yea i read up since i posted that and yea i decided to go with just want you said lol thanks for the in4


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## Trawe (Aug 21, 2008)

converseking said:


> how well do u think it'll go if i skip he 600 watt hps and jus go for a 1000 with 16 plants? i hear 1000watts is jus right for a 4x4 space. and what do you think about areoponice hydro systems? i was thinking of gettin (2) 8 plants systems instead of the DWC's and puttin them in a 4x4 grow tent as well( they would take up a 3x4 space side by side) im jus not sure if if they'd be worth the extra money but some one told me they where the best and hardest to use of all hydo's. any input on any of this would be a great help.


400 is more than adequate for such a small space, keep in mind the sides are reflective. I have a 600 and trust me, I worry about heat even with a 470 CFM exhaust. a 1000 watter in a 4x4x8 might start frying shit. I dont know... check out my grow:


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## bongrippinbob (Aug 21, 2008)

If you have all the correct ventilation and an air cooled hood, I would say get a 1000 watt light. I have a 420cfm fan for my light and a 465cfm fan for exhaust. My temps stay about 4-6 degrees above ambient temps. 
As long as you can keep it cool, you will be much better off with the 1000watt light. I used to use a 400watt light in a 2'x2' area for like 2 yrs without any problems. ANd that was with a cheap batwing reflector. I just built a 4'x4' cab, and I use a 600watt light in there. I am planning on adding another 600watt in there in the near future. So I would have 1200watts in the same size space you are using.
If you can cool the well, you shouldn't have a problem with heat. The only place the heat comes from is the lights. If they are kept cool enough, the rest of the cab will stay cool as well. Or you can always add an A/C unit to your setup as well.


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