The General Illumination Formula

[Jimmy]

You need roughly 50 watts of HPS or MH light per square foot of your grow area.

The simple formula looks like this:

250W HID = 2´x2´area

400W HID = 3´x3´area

600W HID = 3,5´x3,5´area

1kw HID = 4´x4´area

This simple watts-per-square-foot calculation assumes that each square foot of space receives the same lumens, but in reality bulbs do not cast lumens equally to all areas. We need to include depth in our calculation. As light travels away from its source, its intensity diminishes by a factor of one quarter each time the distance travels doubles.

There´s nothing wrong whit using a 1,000-watt HID light on a few plants, or even one plant - they will grow bigger and better for it - but you need to make sure that you choose genetics that can use all the available light. Lightning overkill occurs when a single strong HID light is used to grow a genetically poor yielding strain. You will find that a single 400-watt HID may been more than enough to grow the strain to optimal maturity. Most strains available from reputable breeders are high-yielding plants, which is why growers can sometime use a single 1,000-watt light and pull two pounds or more of bud from the one plant.

The other issue is cost. Do you really want to spend all that money on lightning and electricity? HID lights range in price from anywhere between $220 and $700 for a full kit. A 600-watt HPS kit should cost about $250: money well spent if you want great plants with big buds.

Over time, you will understand more about grow rooms and how to light them properly. Whit experience, you should be able to tell intuitively which light suite your needs. As a general rule, when in doubt buy a 400-watt HPS or better. Even a 250-watt HPS can get you good-size buds, but going below that mark will yield you less than average results. Most growers use a 600-watt HPS for better results. 1,000-watt light provide the best yields indoors but consume more $$$$$.

Hey friends and hunters. I direct copy this text from The Cannabis grow bible by Greg Green.

Peace

Jimmy

[domnic0723]

Thanks for sharing.

I would like to say your spent growing as your plants growing

That is why we are trying to Improve the efficiency of the Grow Light .

[BC farmer]

Excellent explanation..