New grower, looking for a little room setup advice

[KidFrankie]

Hi all, thank you in advance for any advice or insight you can provide. I have a few grows under my belt using CFLs, but I've decided to upgrade to a MH/HPS setup for better yields and results. Unfortunately for me it's not quite as simple as switching out the lighting. The closet I use for my grow space has no air vents in it, so especially when I have to close it up during 12/12 it can get a little warm in there with minimal air flow. I've read online that MH/HPS lights give off more heat than CFLs, but I didn't know if replacing 8 CFLs with only one MH or HPS bulb would still increase the heat of the room. Some of the options I've looked into are getting a grow tent, or getting a portable AC unit for the room to keep the temperature down. I was also curious how important a ventilation setup is when using MH/HPS light. Is it absolutely necessary or only recommended? By the way my closet is approximately 5'x5'x8'. Any other setups you know that might work for my situation would be great to hear.

Thanks,

The Kid

 

[Graytail]

I have a 4x4x7 room, and I recently switched from almost 500 watts of CFLs to a 600 watt hps. I get by with a 4 inch vent and a 50 cfm fan/duct, but my room is concrete block sunk 5 feet into the ground, that block is never gonna heat up, so I have an advantage. If I have to vent, you're going to have to vent.

The hps definitely puts out more heat than the big CFL rig. It amounted to about 4 degrees extra in my space with the 50 cfm 4 inch vent - I run at 82 day and 75 night, stable, because the passive intake is fed from a 75 degree room. You have more space so it'll take longer to saturate it, but you'll still hit the high 80s if you can't get some cold air in there somehow.

That's a great space you have if you can control the environment - nice size!

 

[Coke420]

Your going to need an inline fan for sure go with a 600 watt hps tho

 

[KidFrankie]

One of my biggest problems has been controlling the temp of the room, which is a result of my inability to provide the optimal environment. Without any sort of A/C vent in the room the only way I'm able to keep the temperature down is with the fan in the room and by keeping the door open when lights are on. Since I don't have any vent in the room, I don't know where I could put the exhaust when lights are off and the door is closed. Also, the reason I'm considering a 400 watt over a 600 is because I only grow 1 plant at a time so 600 seems like overkill, especially giving my grow room issues.

 

[Graytail]

Well, I can tell you that I just went through the light choices myself and settled on the 600 watt - more lumens/watt which also mean less heat/watt, and the 600 is also the best cost/watt. Your space is bigger than mine, and I'm considering another 600 watts for my 4x4 for 1200 total. I'd like to get over 50 watts of HID per sq ft, which is in the optimum range. Keep an eye on ebay. I sniped a system for 139 shipped. Turn the ballast down to manage heat if you want to.

Is the room you open the door into cool? Maybe you could rig up a vent in the door? You don't need to vent when the lights are off.

[edit] wait ... one plant? Heheh, yeah, 400 will do it. You could really do a good job with one big sativa in there!

 

[BillZ]

My closet I'm using is 5' wide x 2.5' deep x 6' high. For exhaust it is a 120 CFM 4" Duct Fan in top right corner of closet. For inflow I cut the bottom 1/2" off the door leaving a 5/8" high by 30" wide sliver under the door. The bedroom has HVAC duct and kept at 78 degrees.
I exhaust the closet almost directly under one of the air conditioning ducts which will circulate the air whenever it cycles on. For lights I have 2 4FT homemade CFL fixtures each with 16 23W bulbs totally 32 23W bulbs or 768 watts. I can use any combination of number of bulbs depending on plant and container size. Seedlings I can put two rows of 20 (start with 40 plants and cull when transplanting) 18oz soho cups against the back wall and use only 8 bulbs the first couple days then increasing to 12 bulbs for day 6 thru day 16. Then add another 4 on for days 17-24 and 1st transplant (cull top 20) 1 gal containers on day 17; add another 4 day 25-35; 2nd transplant day 30 cull 10 down to 10 plants. Add 4 day 36 - 42; add remaining 4 end of day 42 and transplant to 5 gal pots thereby reaching my max 32 bulbs at end of week 6 veg cycle. Grow 2 more weeks under this and switch out my daylight bulbs to 2700K for flowering. I will clone at end of week 7 veg cycle and put clones under 40W 4 ft tubes 12 on 12 off; see what sex each plant is and all plants are numbered. That way when I switch to 12 on 12 off for the plants I know which ones to keep as females (5) and which to kill and consume as males that haven't quite reached maturity or producing pollen. Even the leaves of males at two months can give a half decent buzz.

 

[KidFrankie]

I think the other part to the total picture I neglected to mention was that I also have a dehumidifier running in there. It does give off some heat when it's running which I think also contributes to my temperature problems. The room I open the door to is cool though, and there's a vent right outside the door on the wall.

 

[Graytail]

Yeah, the dehumidifier is a problem - they put out a lot of heat. If you vent the closet, you can move it out into the room, since that's where the cool (and dry) passive air will be coming from.