The Classic 400 Watt Versus 1000 Watt Debate

Raw Power

I would like your input on this subject.(I already have my own opinion formed) What final yield differences have you had or think would have from using a 400 Watt HID light versus a 1000 watt HID light? We don't have to get into the differences of horizontal reflectors compared to parabolic reflectors. Just theroretical or factual yield differences.

Myself I prefer to use 3-400w lights for a couple of reasons.

1) I get an extra 200w of light

2) If I lose a light or ballast I still have 800w compared to "0" if I just had one 1000w lamp.

3) I can position the lamps so they are on top and to the sides of the plants.


I never compared a yield but I would guess with the right lamp positioning, it would give a greater yield due to the intensity of the light in the lower regions of the plant. :twocents:

as someone once said somewhere......
1000 watt lamps can penetrate the canopy much better than a lower wattage could. its like a fire hose vs a regular hose

I would go with the 3 400Watters. Your light footprint can be much better spread out.

I also liked Psyscho's redundancy argument. It would suck to have your single 1000W bulb go 'puufff'....

Gotta always keep a spare bro. Always.

Quote:

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Originally Posted by Psycho4Bud

3) I can position the lamps so they are on top and to the sides of the plants.

I never compared a yield but I would guess with the right lamp positioning, it would give a greater yield due to the intensity of the light in the lower regions of the plant. :twocents:

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This was exactly what I wanted to say. Except I do it with just two 400W lamps. Two points of light (or 3!) will give a better light distribution. That 1000W lamp may be putting out 140,000 lumens, but if it is the only point of light over many plants, it's too far away from some of the plants to be any more effective than an incandescent. Light degrades exponentially from it's point of origin.

I have one of those Super Spectrum lights which is 2 - 400 watters in one reflector. I also have a 1000 watt with a very similar reflector to the Super Spectrum. I have them on one of those sun twist's they no longer make. It should be noted that there is some overlapping light. All of the other factors are pretty much the same as far as ferts, light distance, ect. (the super spectrum heats up almost as much as the 1000 watter anyways) In this case yields were pretty much the same on identical plants. I really didn't notice much of a difference in growth rate ect.

Herbus