Should i use a 600w or 1000w?

I am going to be doing a 20 plant sog in a 5x5 6x6 60" 60" 80" tent, will a 600w hps be enough? Or should i go for a 1000w?

can someone help me this is kind of important?

I would use a 1000 because you are probably gonna need to cover the entire room and I believe a 600 only affectivley covers 4x4 area

I second the 1000... get a dimmable, so if you wanna create less heat, and use less power and have less than a full tent at first you can switch it down to 500 or 750 watts if you don't need the full 1000 right off the get go... I just got a 1000, similar diamentions as yours except taller, for the 6-7 plants i got in there im not even using full power.

I'll chime in with a vote for a dimable/switchable ballast. I run a 500/750/1000 digital on 10 plants that I vegged for nearly 3 mos. so the room is filling up fast and flipped nearly 3 wks. ago with some super cropping late in veg. Working very well for me so far.

1000 watter. Or maybe two 600's/

i picked up a 1000w, and was running just over 20 plants until they were sexed, now down to 8, if I had all females there would be no way they would all be getting enough light. I believe a 1000w with a XXXL Hood covers around 5 ft x 5 ft.. If they all made it to this size... theres no way 1 x 1000w would do it justice. I would recommend 2 600's if you can, or 2 1000w