I did a cool tube and it gave saved my temps by 10 degrees it would work better but I need a stronger exhuast fan. Oh to make a cool tube just use this its a really good way to make a cool tube http://boards.cannabis.com/showthread.php?t=38520:thumbsup: oh in order to cool ur 600 watt bulb you would need at least 240 CFM exhuast fan to work well. I'm only using a 80CFM for a 400w thats y mine isnt working well I need at least 160cfm for my 400.

You can also check out Turtle420 thread :thumbsup:http://boards.cannabis.com/showthrea...t=34726&page=6