250 or 400 hps?

starting new grow i have an area bout 30 inches tall about 15 inches front to back side to side. i was thinking a 400 watt HPS would be to hot for the little amount of area any suggestions? or should i go with the 250 watt?

for that area you should go with a 70-150 watt hps. a 250 is for 2x2 foot area. 400 watter would be good for 4x4. 250 are great lights but i would reccomend a 400 watter IF YOU HAVE THE ROOM?

Hard to answer that without knowing what type, if any, of venting you're planning on.

you should go with the 400 wat, but with a cool tube hood..... lots of ventalation too.... you'll have killer shit if its not to hot.

You should check out our 400 watt grow... area is bigger ( 4'W*3'H*2'D) and we have two intake fans one exhaust and a fan inside there and its tough keeping the temp under 90F. We have to crack the doors a few times a day for an hour or so... definitely going to get a cool tube as soon as we can afford it. This is our first grow so definitely noobs but unless you have a cool tube and an awful lot of fans (solid walls of fans maybe?) you'd probably have a lot less headache with the 250 or less maybe... we would have exchanged ours but too expensive with the shipping to where we are so we're trying to make it work... going okay so far though I guess.

get the 400, i bought a 400 and wish i had a 600

250 top after 5th node

probbally going to be using 4 120mm pc fans on 12v 2 intake 2 outtake, can add more fan in needed. Im going to get the exact measurement today but that is roughly the size.

chitownsmoking said:

for that area you should go with a 70-150 watt hps. a 250 is for 2x2 foot area. 400 watter would be good for 4x4. 250 are great lights but i would reccomend a 400 watter IF YOU HAVE THE ROOM?

Click to expand...

for a smaller room its good for the 250w also because of the heat issue/.

I'd go with a 250 to avoid heat issues. Since you're dealing with height restrictions, you'll be able to grow them a bit taller without burning them to boot.

Heat is always an issue. As a result I'm researching 90 watt LED UFOs and other designs. I've found a little research specific to our favorite plant and the 90 watt UFO.
Now I see there's a 225-LED panel that uses 14 watts. Anybody looking into that?

only way a 250 will work in that area is with some major ventaliation-

with the ventilation you are talking about, you will not be able to run any decent sized hps in that area. Even a 250 in an area that small will turn that box into a sauna, or probably more of a desert. It will be very hot and your plants will suck up water instantly. You are going to end up burning down yourparents house.

i made an attachment to the growing area, spot for a light on the top of the box, im going to put 2 fans i have around the house on either side one in, one out. Im not sure namebrand or cfm but the fans are 6 inches. Plus still 4 120mm pc fans.

would a 250w still produce too much heat? Or should i stick with cfl's

No point in using the 2 fans with one intake and one exhaust. Make them both exhaust and just use passive intake, just about twice as much airflow. But I still say 250 is still going to be too much for that space.

isn't that basically PC sized or around there? I'm thinking a 250 will be too much

I accept with information:Hard to answer that without knowing what type, if any, of venting you're planning on.

i measured the growing area.. its 42inches high plus another 8 for the place for the lights, 21 front to back and 18 side to side. What is passive intake? 2 exhaust fans and...?

2 exhaust fans and a hole, or just shoddy enough construction to let air in through edges and whatnot. It just means that if you are blowing air out, air will find a way in. Have you considered the filtering system for scent through this venting as well, cuz even small plants can give off quite a scent. At 42 in. from floor to light you may be able to manage a 250 but certainly not more. considering the fact that your pots will take up atleast 5-6 vertical inches and you will need to keep the plant atleast 3-4 in. from the light (probably much more depending on temps and if you have a shield over the lamp). If you do decide (which you probably should) to have the lamp in either a cool tube or some other form of shielded hood, you will also have to figure out how you want to vent the hood. These are all important things you should figure out before you even begin gathering your supplies.