You gonna need alot bigger fan than that for the 600 my friend.The extraction fan i mean, But thats the way to cool the bulb.It will keep the hot air from just sitting around creating hot spots.Id get a hood for the 600 thats has a tap to hook a duct like a 4inch are 6inch extraction duct to it.Your plants are loving that 600 but your gonna have to get that intake and extraction down are your never gonna mantain desired temp.Makes me wanna fire up another 600 but i like 400s for that reason they are alot easier to maintain desired temp for ME..

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