How many watts in 2x2x5ft tent?

[Nutria]

Hey guys! I want to upgrade the lighting in my flowering tent. Now I am using a MarsHydro led panel that draw about 140w. I grow in an attic (close to my bedroom) and winter is coming (not rly cold, around 0c/32f outside). So I want to use a HID setup, but how many watts? I would buy a 400w dimmable ballast with a 400w HPS but those are too many watts for such a small space. I can dim the bulb to 200w or to 300w and I would be happy to use the led panel too, maybe 200w+130w?
What can you suggest me?

Probably the led panel will be too close to the plants shadowing em.
Tent is small and I have only 2ft between top of the tent and the scrog net

 

[Austin084]

I've been using a 400w HID in much the same space with very good results. I've just gone to leds on account of my ridiculously warm climate, but never had any major dramas using HIDs. Best of luck

 

[Nutria]

During late spring/Summer i can't grow due to high temps. Btw I don't want to pay for extra watts my plants are not using. It's a waste of money but I don't k ow when watts are too much

 

[415friendly]

Mars Hydro says that their Reflector-96 is equivalent to a 250W HID. That's what I use in a 2 x 3 foot space, and I'm already itching to upgrade to a more powerful light. That being said, it would seem that 400W HID would be the next step up. Many 600W ballasts are dimmable to 400W and 250W which might give you room to grow in the future (ah, did you see what I did there? )