400HPS vs 600 HPS heat, penetration

[Thebogie]

New grow box made outa a Gun Safe. Insde is 20x28 x 5 ft. Thinking a 600HPS cooltube for better penetration etc. 2 6' inch filtered entry & 1 6" exit fan carb. filter after going through tube. (can go 8") with 2 small oscillatting fans.
Peace and hope all "break even" on XMAS LOL