Yeah man....
I agree with the idea of air cooled lights....
I have a 600 watt HPS 10" away from seedlings... with no problems... temps are 72.1 as I look at the thermometer while typing...
I use a 4", 170 CFM centriugal fan, dedicated to the light, 4" ducts to adapters on the 6" cool tube....
Al B. Fuct runs a 200 CFM fan across 2 x 1000 watt HPS in cool tubes.... one fan for both lights...
As for intake/exhaust, your temperatures will have to guide you....
I am shooting for being able to cool it to 65F in there... and control the temp with fan speed controllers... that way I say what the temp is going to be...
Also important is to remember that you want a slight vacuum in your tent.... so fresh air leaks in....
You do not want your tent pressurizing, ballooning... intake should be about 2/3 CFM than exhaust....
I want to harvest the best I can produce... so I am a believer of over lighting followed by some over venting...
But that is just me... and my 600 watt 36x20x60 home made tent
Hope this helps... holler if you got any questions...
Best of Luck...
Gypsy...
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