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Thread: lumens

  1. #1
    Burnout is offline Registered
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    lumens

    how many lumens would i need for my grow room my grow room is small and only growing one plant, im still researching a fluro for cheap i can purchase at ace hard ware or home depot and also what color white or blue

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  3. #2
    GTC21's Avatar
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    I found this on a grow guide -

    Now for the big question. How much light do I need? Technology has advanced so much in the last 15 years that we are constantly refining the process and updating what we know works best for growing. Current theory holds that the minimum amount of lighting needed to sustain growth is around 2000 lumens per square foot. Mid range is around 5000 lumens per square foot. Optimal is 7000-7500, or higher, lumens per square foot.

    As for types of fluorescent, you need both really, cool and warm. The cool ones are used for vegetative growth because they emit more blue light, and the warm ones are used in flowering because they emit more red light.
    Do some more research on the internet before you buy anything.

  4. #3
    Zandor's Avatar
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    I still say those numbers are minimum not Optimal. The math is still the same even though technology is improving the math is still the same. Flouriest light works it just does not put out enough for a good quality grow. For 1 to 4 plants for one person it's fine. You can't use COČ with fluorescents there is not enough lumens produced for the plant to process the extra COČ.

    For clones yes....for mothers...ok....for a first grow or two.....fine......for the long haul.....no way. The math does not support using florescent lights for quality grows. Plants stretch, buds are smaller, THC content is not as high in % VS HPS.

    Lumens is a mathematical formula that measures the bulbs intensity at 1 foot. The color or type of bulb is not calculated in the formula I=L/DČ Lumens received are a measured in watts-per-square foot or foot-candles. Calculating foot-candles or lux is a more accurate way to estimate the amount of light plants receive. This still only measures how much light you plants have available but not how much your plants use. Light diminishes exponentially fast!
    The closer your plants are to the light the more lumens they receive the better they will grow, as long as the heat from the light does not burn the foliage.
    Peace
    Zandor

    If you go cheap you grow cheap. - Me

  5. #4
    Burnout is offline Registered
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    damn zandor is the smaretes grower ive ever seen

  6. #5
    Zero Revolt's Avatar
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    Zandor don't forget lumens are decreased at an exponantial rate the further the light is away from the plants. As a general rule of thumb cannabis likes the same tempature we do. To be exact the range for good growth is between 65f and 85f with 75f being optimal sometimes just a little warmer will speed growth somewhat. But going over 85f will most certainly stunt growth unless you are implementing CO2 which if that is the case you can sucsessfully raise the tempatures to around 90f and 95f for a longer period of time as long as you are giving the plants CO2 at regular intervals. To make it simple to see if you think the light is too close to your plants place your hand just over the top of your plants for about one minuite and if you cant take the heat neither can they. I personally have a 400watt HPS system and I distance my light away from my plants 18 inches and I get superior growth although I do use 2 mil thick mylar to recover lumens that would otherwise be lost. If you have to use fluro's use cool white tubes for vegatative growth and warm white for flowering. Fluro's must be no further than 2 inches away from the tops of the plants to receive optimal lumen coverage.This is bare bones but the minimum amount of lumens per square foot should never be less than 200 and buds grown under fluros are always small light airy and not very potent. good luck.
    Last edited by Zero Revolt; Jun-17-2005 at 13:39.
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