How much light can I use?

Howdy everyone. I currently grow with a 400 watt hps but I am thinking about upgrading to get the most out of my harvest. From what I have read, 1000 watts would be way to hot for my area (3x3). However, I run the ballast outside the tent and I can easily keep the temperatures at or below 70 degrees right now because I have decent ventilation. So is the general consensus still to only go with 600? I just don't want to upgrade to the 600 only to find that I could have handled the 1000 watt light. Anyone had success with 1000 watts in a small area? Any input would be greatly appreciated.

Also, I am about 21 days into 12/12 on my current grow of mazar and ak47. I will try to get some picks up soon

if you got the heat issue under control, i would say to go with the 1000w... i mean, you are trying to mimic the sun

Light never burnd a plant it is the heat the light gives off. If you keep the room cool you can have as much light as you want. You might have to use co2 for the plants to actually use all the light you give them though..

Get and Air Cooled hood and run whatever you like!

If you get a vented hood and have good air circulation go for a 600 watt, im guessing by the size of your tent you have about 4 plants i think 1000 watt might be over doing it unless you can see yourself expanding

Hmmm so two for the 1000 watter and 1 for the 600. Thanks for the input everyone, I do have an aircooled hood and yes joe your right about having 4 plants. I cannot afford CO2 right now unfortunately. I won't be expanding anytime soon. So I guess I am still a bit undecided but leaning towards 600 watts, thanks again for the input and hopefully I can get some more opinions. Anybody know how many degrees difference I should expect as far as heat output between the 400 and the 1000 watt lights?

I have a 1000hps and use the Solarmax1 bulb (which is a 400mh & a 6oohps in the same bulb) unreal bulb that gives you growth like no other bulb.
You get a vented hood and your laughing.

You get a vented hood and your laughing.[/quote]

get a coolshade and you'll be in hysterics!lol.

Im only guessing but a 1000 w might make up to 5 to 10 degree c more heat, and i dont believe you will notice great difference in yeild going to 1000w over a 600w but im sure you will see the difference in your power bill . I have run 400w hps over 4 plants with fantastic results . just a thought you could wait till your next grow to upgrade your light and this time send your money on Co2 injection kit this will give you much results from your plants than just changing your light .