how far should i keep 400watt light?

how far should i keep 400watt light from a seed i just put in soil. it hasnt even sprouted yet? can some one tell me how far i should keep the light for every stage of growth?

i always kept mine about 12 to 16 inches away from the top of the plant. you can also play with it a little if there is stretching go closer and if leafs are burning go further

put ur hand over the top of the plant... if its not too hot for ur hand, its not too hot for the plant =) if u feel it burning, back it off a lil.... i kept mine about 20" but thats cuz im too lazy to lower it...

for a seed... i would do 3 ft.... or so

if it is comfortable on the back of your hand it is ok for your plants.dont push it though. its better to be safe than sorry.

xxtoadxx said:

for a seed... i would do 3 ft.... or so

Click to expand...

Not recommended to use 400w light during that stage. Use a window or some flouros for about a week then maybe the bigger light a good bit away like toad said. Once they get good and strong you can normally keep a 400w about 14 inches away. You just need to feel your plant and watch its reactions.

do i use mh or hps for veg growth? so keep it about 1 feet away from the soil? i dont want it to stretch. im trying to keep it under a feet tall and im going to leave it on 24/7? i am going to put the put in a 2 feet tall cardboard box and am going to put it in the attic.i was going to put it up there now and leave it on for 24/7 would it catch fire?? there are insulation and things laying around?

Hey Bud, I would not reccomend putting a 400w MH in a CARDBOARD box in an attic with no ventilation in the box, and especially not with loose insulation nearby.

What happens if how you have the ligh supported on the box fails and falls over, the MH Light gets extremely hot, and would be a fire hazzard up there.

I'd goto Home Depot Buy a Clip on Alluminum Light Reflector, and get Some CFL's.

But if you are just starting seeds, not sprouted yet. You do not need light yet.

what do you mean i dont need light? so should i go to home depot and get some wood and make a box like those grow kits and put aluminum foil inside?

I don't want to be critical of your plan, but what you're suggesting could seriously result in your house catching on fire.

If you're going to put a 400W light in your attic AT LEAST build some sort of box for it. My 400W HPS operates at almost 400 degrees fahrenheit. I know because I measured it with an IR thermometer. The transformer is also QUITE hot. That's right around the flashpoint point of a lot of stuff in your attic, including wood. In other words, if your light runs just a little hotter than mine, wood could catch on fire just from touching that bulb. Plus, it's in your attic. Even if you happen to be home when the thing catches on fire, it probably will have been burning for a while before you even realize it.

You also can not seal it up in a box. If it's going to be in a small plywood box, you will also need a lot of air going in and out of the box. If you don't have good ventilation, the bulb will turn your box into an oven. Think easy-bake on steroids.

what should I buy from home depot to grow 2 plants in attic and I have a small budget?

I would Suggest going to Home depot and Looking for this Clamp on Reflector about 8 $
And a Compact Fluorescent or 2.

That's good advice about the clamp on reflector light. You can get one of those and a 42W (150W incandescent equivalent) CFL for under $20. You want that bulb almost literally touching your plant.