I finally broke down and bought a 400w hps/metal halide conversion bulb and i've got 9 plants in veg right now... and decided to switch them from cfl to metal halide... and i spent almost 200$ and i set it all up... put it like 2' above my plants and it scourched one right off the bat... so i set up a different room and put the light almost 4 feet above the plants... put a fan blowing on them and a cool mist humidifier blowing on them to keep it cool... and it still got hotter than f*** in there... and it still scourched 3 more of my plants... and i was checking on them like every hour... so i switched back to my cfls... any advice you can give me... of what i'm doing wrong.. and why it gets soooo hot in there ? oh, i also put two fans on the ballast part of it... hoping it would keep it cool enough it wouldn't heat the room so badly... but it didn't work
if you're using hps you must have antiquate ventilation. pull air in the bottom and push it out the top. if you're moving enough air you won't have a problem with it. if you're not you will. good luck.
my guess is spend the extra and buy a cool tube for that light cause seems like its way to hot in ur location. I've a got a 250w its a basic hps and with 2 vents and a fan its still hot but. Running the lights at night help. maybe its 2 big for your room.
the room is like... 12' x 7' and where can i find a "cool tube" at... i was also curious... the way it scourched my plants.. will they recover ? one of them just seems to be getting worst... and the others... the leaves are just curled a bit... could it also be better once they got bigger ? and would it be different if i started them under that light ? and will they be in shock from being that hot for like 6 hours then going back under a cfl? it's an hps ballast... but it came with a metal halide conversion bulb.. that's the one i used
i think humidity just makes it feel hotter to us... cause sweat doesn't dry on our skin lolz... and the mister is a cool air mister and could the plants just not like it cause they aren't used to it ? cause my plants are so burnt =( even having them almost 4 feet away from the light
ok.. here is the deal.. unless you do one of these two things you are going to have an oven in there.. put a window ac to counter the heat.. or move the ballast away from the light buy an aircooled hood.. and suck the air with a blower through the hood and into a hole in the cieling (pumping the heat into the attic.. ) Other than that you are going to keep producing mad heat that is vented to nowhere but your cooking plants.. Sorry I know it's a shitty realization, specially after spending the money finally on a 400...
I once saw this problem solved by installing a puter fan into the reflector. If it works lots cheaper than a cool tube.
I had the same problem with heat in my space. I bought one of those portable air conditioners from Home Depot. The model I got had a 6" intake and a 6" exaust on the back, built in dehumidifier and fan, the panel is all digital, with timers and everything. Just set it to auto and be worry free. Cost and noise are a bit of an issue, however, very effective. http://www.danby.ca/en/productDetails.asp?model_no=DPAC10071&dept=0004
well i don't have a window in there.. it's a laundry room... with a dryer vent and only one door... but theres a door to the attic built in the ceiling
As no one has seemed to bother to ask, what is your present ventilation system like? You can not run a 400 watt light in a confined space without paying attention to your ventilation system - its just not that easy. You should be spending as much, or more, money on climate control that on lighting. In all likelyness, your going to need a system that moves at least 100 cubic feet of air per minute out of the room (and the same amount of fresh air into it). As mentioned, a cool tube is also another option (in addition to ventilation, not as a replacement), but you might want to keep it simple for the time being. A cool tube is going to require you to use ducting, which is going to necessitate extra fans, etc. It's really difficult to offer any input without knowing the details of your grow room. But to bluntly answer your question "why is it so hot in there", its because the heat has no where to go.
well... i know why it's hot in there... it's just... i have a 20" fan blowing air in the bottom half of the door now... and bought some dryer vent ducting or whatever... and hooked it from right under the light... to the exhaust you find above the stove... and put a small fan under the light.. and hooked it to the other end of the ducting... and that still isn't helping so i guess ima just have to sell this light... too much for me... besides i'm only wanting 3 plants to get big at most... didn't realize it would be soooooo hot.. i kinda thought.. (from pictures/posts) that these lights wouldn't be much hotter than a flood light... didn't realize it was sunlight put into a bulb lolz... husband said it looks like the beam that abducts people from an UFO... oh yea... put a thermometer in there.. and it was 115 lolz.... well, if anyone interested in buying this light... it's still brand new... i'll sell it for $180 shipped both bulbs as well... (mh conversion, hps) 400w
wow, 115*F? Is that with the MH or HPS bulb? I have a 400w MH in a 2'x4'x6' cabinet with a 50cfm exhaust at the top and 40cfm intake on the bottom and it only hits maybe 90*F when the ambient temp outside the cabinet is around 76*F. Granted, this is still to hot, but I have an air-coolable hood which I will be hooking a 172cfm exhaust fan up to - if that doesn't do the trick, nothing will.
Man I have a 400w HPS in a small closet and about 8' inches from the canopy, my room temp is about 26c... I have 2 180CFM fans taking air out, passive intake... and a small fan ... You need to get the air out, especially from around the bulb...
It's sad but simple. Either you get enough air flowing through the room or you go to a smaller light or more cfl's. If you could swap the 400W back in and get a 250W, you could run a 270W Hps with added blue for the entire grow. In your 400W, you could burn a 430W HPS with added blue. HPS lights run cooler than MH. Other than that you are facing a lot of duct work, etc. Pigailia