It depends on many factors. If you have a cool tube with good sucking/blowing power, you can have your light right in the plants. If you have an open light with no fan blowing on it, you had better keep a 1000 watter a couple of feet away at least to start. See how that works for awhile as you watch the plants closely. Put your hand next to the tops of the plants and see how hot it is. If it is uncomfortable for your hand, it will probably be so for the plants too, and they will rebel somehow. Keep moving your light closer and closer, checking and watching each time. As soon as you see any sign of light or heat stress, pull it back 2 or 3 inches and keep it that far away from the plants at all times. A little testing in the beggining, and you will know forever, unless you buy a different brand bulb, or your ventilation starts to get plugged up somehow, like at the filter.

Also, if you get your light too close, it may not cover the outer areas of the grow as well. Watch that too.
Opie Yutts Reviewed by Opie Yutts on . HELP QUICK PLEASE lamp closeness how far from my plants should my lamp be its a 1000 watt plant where should it be ??a foot above it or 2 feet or what i want best light and everything for the plants please help? Rating: 5