Quote Originally Posted by Rusty Trichome
A 400w light will have an effective range of almost 3 feet. For young clones and seedlings, 2 1/2 feet is fine. Once clones are rooted, or seedlings are well-established...ok to start lowering the lights. (hardens them up to the increasing light intensity) After about a week of hardening them up, I keep my lights within about a foot, until harvest, but your ambient room temps will determine what you can get away with there.

In flower, I would take the fans off the light timer, if it's on the same circuit. With high humidity, you'll want the fans on 24/7. In flower, 70% humidity is not fine. The lower, the better. I live in the desert, and summertime humidity stays around 10%. The ladies love it.
In veg, the plants like humidity a tad higher anyway, but keep an eye open for mold, just the same.
thanx rusty for the info, im gonna so exactly waht you say about the lights. ever since i moved them up towards the light they have gotten much bigger and thicker on the stems, at the moment i keep the fans on 24/7 do to heat/humidity and these fruit flies that seem to think they can destroy my plants..
doomie62 Reviewed by doomie62 on . First Grow In South Africa.. Help appreciated Well iv have decided to grow some nice indoor Cronic, and i got hold of white rhino seeds off of rhino-seed's.com and i have built a big grow house dimensions are (5 feet tall-3 feet wide) for light im using a 400watt Metal Halide for Veg and a 400watt HPS for Flowering.. for ventilation i have got one main extractor fan that push's cold air into the box, and two very powerful 120mm fans to circulate air. for soil i have gone for basic potting mix the best i could find.. i started the grow on 7 Rating: 5