Indoor lighting question

what would be better for stopping heat 4 x 600 HPS 2 x 1000 HPS only have 4 pots hydro in a shed 1.2 x 3 x 1.8

An area 1.2 x 3m would suit 2 x 600Watt lights.
If you wanted to put 3 600’s in there do it when the temperatures are under control.
Use lots of fans, and exchange the air for fresh air
Don’t run it around and around the room.
Good luck
Scott