Twisted's wicked problem

ok, i made my own grow cabinet and am having trouble getting temps down...im hittting 93. im using a 400 hps with a cool tube. please check my pics and throw me some advice. im adding a co2 system so the temps can still be high. the issue then will be res. temps.....so id like to solve the heat prob without co2 as a cure for the heat instead of a yield increaser to get the max benefit of the c02. the exhaust goes into another room and the ambient temp of outside the cabinet is 68.
what fan do i need to get down to good temps? what size ducting?

so nobody?

i have a similar issue with a 400w in a room where i cant control temps, i tossed a 6inch duct fan on it and room is 80F, this is a 250cf fan, if you went and got a 450cfm fan im sure you would be perfect...HTG has a nice 6inch fan for like $120 450cfm, i think its a bargain i been using it since last year and its rock solid

Get a bigger fan

i have an 8 inch 500cfm duct fan that i used on my last grow with a 600. will going from a 6 in cool tube to an 8 inch fan create to much drag? id also have to reduce back down to 6 in on the other side....will this work or should i just get the 6 inch? thanks alot for your time both of you. ill throw some rep your way

If you already have a bigger fan, use it. I have a couple of those lil 100cfm fans they should say 50cfm on them LOL. I dont think you will have any problem reducing it. Good luck and Happy growing

only beef i have with duct fans, if i really need it in a reliable spot, like on my 1000watter i gotta have one of those high cfm inline joints, the duct fans get dust inside and you gotta spray them with wd-40

thanks for the help everyone....i installed the 500 cfm and redid a few things and now i have a custom cool cab with steady temps of 75 and humidity of 50...on top of the success i am 10 for 10 with germed seeds! 3 widow crosses and a couple more goodies! they arent all for the cab at the moment. some are gonna go under a 600 to veg till my aks are done. thanks again!...