Is the $100 ventilation even worth it?

I've got a virtual sun 600 watt grow light with the glass tubing for the light and ventilation hooks so I go out and get a fan a some ducting just got it all hooked up tonight and I don't see much of a temp difference I leave my door open every night for some cool air to breeze on them and it's about the same as every other night so should I take it back it's about 2 or 3 degrees cooler but that's not 100 dollars worth.

Do you even have an intake fan? I think Ventilation is worth it to keep fresh air circulating as long as you have a small intake fan. Plants need all the CO2 they can get while the lights are on.

dude... leaving the door open will be cool, alo of people hav probs cuz its in a room where theres light or something... my bro's veg room has no intake or exaust, runs a plain 400 and some flouros for veg... just keeps the door open and fan blowing..

i have to cool mine or it will be like 100 + degrees in my room.. cause the lights a 2x600 and 1000 on a 6ft lightrail are hot but, with your tent u should be ok if you are keeping the door open, try keeping it closed with and w/out the exaust ans record the temps.. =) and if its in the garage, where its cooler yur ambient temps will b cooler so the tent will be cooler, but youll still need more airflow to exchange air unless you dose with Co2, andi dont do thart

what I've got is on one side a inline duct fan and that's blowing all the hot air from the tube into the ducting which is on the other side and that's linking out to my room this is a closet grow no tent yet and then I've got a big rotating fan bringing in the air from outside and that's the other problem if I close my door which I just did it going to get warmer with no ool air and then they're gonna be lacking co2

well sounds like its a weak fan,, maybe needs to be srtonger, but really, if your not above 85* you dont really need to exaust keep like your ding with opening the door, it would good to look into adding co2 i dont, cause i exaust my air thru a 36" carbon filter then outside 24/7 , but there are lost of options available, sounds like you got a good start best bet is to read and trial and error, it can get exxpensive and there can be a learning curve that puts some people off from doing it, but thats the best to start, you got a closet already so thats a start... i skipped the closet and tent went straigt to my garage..=)keep it all in the air

How many cfm's is your fan? Mines 425 and it clears out a 5'x4'x2' tent in no time. What are the ambient temps from your fresh air coming into your grow space? What are temps at night? I keep my fan/carbon filter on 24/7 and it can get down to 65 degrees no prob if left unattended. Mainly that attributed to me getting fresh air from my attic that is ~40 degrees. Make sure there isn't any gaps or bad bends in your ducting. Make it as much as a straight line as possible. If not, you lose CFM and ability to lower temps.

Not sure if anyone mentioned this...But just the fact that you could get the light closer to the plants makes a cooltube worth it.

I know if I dont have mine running I cant keep my hand on the reflector for more than a couple seconds. With I can just leave my hand there

450 cfm? thats a crapload mines a 6 inch with only 160 and i thought this guys blew some hard air but i think all is swell i closed my door last night to see what happened and not much hanged from other nights its a little above the 70 bar which i figure its under 80 over the plants and that without the door being open for the past 12 hours. i like how u went to a garage right away thats not even a grow room that crossed my mind