I have a 10x10 room, I am only using a 6x6 area of the room and have 3 400w lights over the area. Since the room is 100 sq ft. do I need enough watts and lumens per sq. ft to cover the entire space of the room? Or do I just need enough watts and lumens to cover the 6x6 area my plants are in?
That didn't answer the question, I have 1,200w. But I need to know If the watts and lumens per sq ft. is the sq ft. of the entire room of your grow (even space not being used in the room), or if it is only the space your plants are in. My plants are just in a 6x6 area, but I don't have any mylar or anything around the room that keeps the light in, so If you need enough watts and lumens per sq ft. to cover the entire room than obviously I'll need another light. But, if the watts and lumens per sq. ft is just the square footage of the plants area It should be ok.
You need enough lumens to cover yoru 6x6 grow area, but build some kind of barrier around your plants to maximize your lighting. Cardboard and tin foil is something temporary that would be a big help. These plants are in a large room, but they have a barrier to help maximize light efficiency, 4x5 area once enclosed with x4 plants under x2 600W HPS. Unless you are doing a micro grow, I would recommend a square foot per plant. Good Luck!
Ok, my current setup is just in a bedroom but the room is 10x10. I have a plastic sealed enclosure around a 9x7 area, so can I just staple mylar to the plastic to keep the light in the plastic area?
yea mylar on plastic enclosure would help since it blocks the light from escaping and reflects it back to the plants.
One 400Watt is perfect for 3 x 3 space. However you can get away with a 4 x 4 if you have a grow tent. But then again, you want 'Optimum' I'd say 3 x 3. So three 400Watts should be fair for a 10 x 10. You should focus in what are you going to do in order to increase your 'Yield'. Remember the lights will do its job. You have to do yours ! Rails for those 3 lights should give an idea.
Adding the mylar will make the plastic area a 10x6 area, even with that I am getting just 20W per sq ft. right? I'm confused by the whole watts pr sq ft, I would think if I had 3 400w lights directly over a 6x6 area of plants that it would be plenty of light. But I was told that I don't have enough light per sq ft. with my setup?
3 400w over a 6x6 area will work, but you just can't grow big plants. Move the walls in closer, you could even install a circular pole around the grow area and hang a curtain/plastic/mylar like a shower curtain. Try to get the 10x6 down to 4x4 or 5x5. Like I said it will work, that is enough light to grow, but 20w per square foot will not give you monster plants, monster buds, and will result in slower growth.
The plants are already all between 13-18in. and still have about 6 weeks left. So I'm anticipating some 40in. plants! That's pretty big, but I think if I can get the area to right around 40 sq ft I should be ok, the buds will be mostly above the bottom half of the plant anyways
See the grow through, if your buds are small or fluffy, try less/smaller plants or more light. The idea is to get better with each grow, no setup is perfect the first time around. These plants are resilient and I'm sure you will be rewarded for your efforts.
I think I'm going to try to build a squared box out of carbboard but just build the 4 walls and build them about 6ft tall, I did some measuring and I can fit the plants inside a 7x5 area, and I can leave one of the corners of the square kept open so I can be able to get to the plants easier to water them and be able to get to the plants easier. With six foot tall walls and mylar on the inside of the walls I will have 35sq ft. covered with 3 400w's. I think it's time to go get some supplies and get this thing built!