Please help me out here. I am growing in a box the 2'wx2'dx3't. I have two plants inside currently that I am experimenting with under 6 CFL all 23 watt (actual). I know that this is not enough light but as it is, I am having issues with heat. I have one 4" intake down low , one 4" exhaust on the back wall mid way up and one 4" exhaust on side wall up top. I also have two more passive vents on the box as well. My temps inside the box spiked up today to 86 degrees! The temp in the room is 77. How can I get my temps inside the box down to where they should be? I originally had one of the exhaust fans as an intake but a member here advised me to have more exhaust than intake so I turned one into exhaust. It does not seem to be helping. Please advise! Thanks!
try and dedicate one of your exhaust fans to just venting the lights. possibly a clear barrier between the lights and plants to help focus your exhaust on the lights
Yes, I have one intake that is on a 4" 80CFM fan and two exhausts that are on 4" 80cfm fans also...along with the two other passive vents. I have been told that anything over 80 degrees is bad for growing?
My grow box has been between 80-85 since they were small and they have adapted and grown prefectly fine. Mj plants can withstand a fair amount of heat, and still grow. Just think about how outdoor plant grow in 100+ degrees. But try putting all your fans as intake fans and let the passive holes for exahust. If it doesnt work try it vise versa. goodluck
your intake should be double the size of your exhaust...sounds like a bitch cuz of light proofing, but it does make a difference...you said temps are 77 outside the box right? try to lower that down to 70-73 and that will take care of most of the heat...even cfl's give off heat...from my experience the 4-6 23w cfls can raise about 8-15dF..especially now that its summer... and you want all your exhaust holes to have a fan. you can add fans to your intake, but do not remove them to put them on the intake. is your box in a closet?
My box is in a closet that I moved from my bedroom. I had heat problems when it was in the bedroom also. If anything, I have been getting it a bit cooler since moving it into the closet because there is a heat/air condition vent in there.
What's the surrounding area like ventilation-wise, and what are the temps? With two 4" fans you might experiment with more passive intake; without enough intake there's only so much air they can move. You could also move one of the fans to blow air into the cab, as an active intake. Mid 80s is not bad tempwise. MJ likes warm temps. My last grow was in the mid 90s (sometimes spiked to 99) and everything was fine. It's a pretty hard plant to screw up
The hot air still has to go somewhere, and unless there's a return air vent somewhere nearby it just hangs out in the closet. But the A/C should help. Like I said 85 isn't bad.
If mid-80s is okay then I guess I can go ahead and move on to my next issue (soil)...has anyone ever had problems with your plants stretching out as a result of heat?
Plants shouldn't stretch because of soil (at least not that i've ever heard). Stretching most often occurs because a weak light source is too far away so the plants are trying to get closer to it. This happens a lot with CFLs since they don't have nearly the penetration power of HID lights. Because of this, keep your CFLs as close as possible (a few inches) to the plants. Careful not to burn them
86 degrees isnt bad. Make sure your plants are closest to the ground.. as we all know.. heat rises. Install an exaust fan.. a small computer fan would probably do... Temps are fine up to 90-95. Once you hit 95 and over its starting to hurt the plant. Then again.. some strains will do better/worse under hot conditions.
Thanks for advice guys! I have my CFLs close to the plants so hopefully Im good there now. How much more of an increase in temp do you all think that I would be getting if I switch over to HID lights?