Cfm Question.. Plain and simple..

How much cfm would you recommend to keep a 250 hps with cooltube cool to the touch?

damn 52 views and not one reply... Someone must know this..

What size cooltube? 6" or 8" I'd say a minimum of 150 cfm for the cooltube itself if you are running the cooltube seperate from the room exhaust. I say so much since you want cool to touch

Its for a 6inch.. Reason i need it cool to the touch is because the space is only 2 ft tall, i will be growing autoflowers so i should be fine but i just dont want them to burn if they stretch over night or something..


Thanks for the info.

Damn no more advice?

dude if its a 6" cool tube, get a 6" fan. whatever one you get will move enough air to keep the light cool, 6" fans are strong. i have a 4" cool tube with a 4" fan which moves 190 cfm and its not cool to the touch but a little warm. a 6" fan will move waaay more air, your light is less hot, and the distance between the bulb and the tube itself is a lot further for you so it will be way cooler by default. hit up ebay and get a 6" inline fan. not just one of those duct boosters though those are weak

id go with a 6" with around 400CFM i have a 600HPS in a cool tube with a 6"vortex that pulls 455CFM and its still hot to the touch
so i think a 4" for your application would leave it pretty warm
do you only have 2' total or 2' under the tube?

Well i have a 435 cfm fan cooling my 400w hps and i think im just going to connect the ducting to both and use the one fan..

Yeah i have 2ft under the cooltube, Im just using it for small autoflowers..