600W vs 400W in tent

Hello all=)

Going to buy new lightning for my tent and i wonder what is most suitable 400W or 600W?
Measures: 150 x 150 x 200 cm
Link to tent: http://www.professionalgrow.se/sv/secret-jardin-dark-street-ii-150-x-150-x-200-cm

Personally I think 400W is more than enough The heat is already a small problem, and I currently use LED`s^^

you could use either, assuming you ran the right equipment in addition to just the lights. for example, a cool tube or air cooled hood and inline fan would probably get the job done... I'm sure you already realized that an inline fan is necessary for a tent grow with either a 400 or 600 watt but the air cooled or cool tube hood would make a world of difference in terms of managing your interior heat temps. the key is getting the right stuff so that it all works in conjunction with one another to create an all-around optimal growing condition

I would always suggest the higher wattage light. As long as all other conditions in your tent are in sync, your light will ultimately be the only limiting factor. 600s are the most efficient at turning electricity into lumen output, and they are not much hotter than a 400. Buds grown under a 600 can compete with those grown under a 1000w. This isn't true with a 400.

Just my opinion. Good luck!

I would go with 600w as long as you can control the temps. I run a 400w in a much smaller space.

From my limited exp. I'd agree with most of the rest...go with the 600. If you're using an air cooled hood w/inline, there shouldn't be a huge diff. in the higher temp. from the 400-to-600. Plus...I look at 600 compared to 750 and 1K fairly often and can't even imagine of how much loss of light 'intensity'/penetration there is with only a 400 watt?!

Thanks a lot for good answers. most helpful! going to buy the 600w