How close is too close?

Yesterday the temperature here was considerably cooler outside, that means cooler in my house and cooler in my flowering chamber. I have a couple of thermometers in there in key places and my temps are now optimal. I figured i would try to take advantage of this and get the 400w hps closer. The closest plant top was 7 inches from the center of the light and the rest were slightly farther away. I monitored things closely several times during the day and it appeared that they are very happy with the light that close.

Today when the light came on i went to have a look and they are looking perky and happy like usual. Another cool day so i will keep that 400w close like i did yesterday. I wonder how the plants will benefit from this? I was just had a look at this chart and almost shit myself when i noticed the difference in the amount of lumen output between 6 and 12 inches!! WOW! I am using a hortilux 400w 55,000 lumen bulb.

Tell me more about your temps please..

SuMsHaDy said:

Tell me more about your temps please..

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What do you want to know?

What's the temperature on a cool day, what's the temperature when it's optimal, what's the temperature the rest of the time?

I believe the question is simply, what are your temps

What is the normal range you keep the room ?

What is the outside temp normally and what does it fall to at night ?

How does the above effect your room temps ?

I am new but thinking ahead. My house and room can fall into 60's at night, this could be a problem in flower, when the light is off.

see the link? why don't you look in his journal?

oh MT they should be fine. if you see them starting to curl back it off.

SuMsHaDy said:

What is the normal range you keep the room ?

What is the outside temp normally and what does it fall to at night ?

How does the above effect your room temps ?

I am new but thinking ahead. My house and room can fall into 60's at night, this could be a problem in flower, when the light is off.

Click to expand...

1. This time of year my temps are usually on the high side because it's so hot out. 27-29c is what i have been seeing until a few days ago.

2. This time of year the outside temps are usually around 30c or higher, and in the evening around low to mid 20's.


3. I don't live in a airconditioned house so when it's a hot ass sunny day outside it's almost as hot inside, and when it's cooler outside it's cooler inside. You following? I have a active air intake to my sealed flowering room (closet) which pulls fresh air in from the main room. You got that? If the main room is cooler like on a cooler day that means my active air intake is pumping cooler air into my flowering chamber, which inturn brings down the temperature. Make sense?

some people swear by the method of keeping a 400 no farther than 8 inches,they dont even put a 1000 at more then 12.as long as you have a fan sweeping across the top.ive read over a hundred grow journals in the past while,and alot of people like the 6"from light with a 400.but then others like it farther away,so what im saying is that it shouldnt hurt it,and penetrate better.but wait for responces from people who use the 400.