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HOME + GROW INFORMATION + GROW LIGHTS INFORMATION

INFORMATION: GROW LIGHTS

introduction to light
Photosynthesis
introduction to HID grow lights
digital ballasts
HID bulbs
Caring for HID bulbs
A note about Lumens
Metal Halides and Hps
fluorescents
High Output (T5) Fluorescents
Compact Fluorescents

Working With Indoor Grow lights
Maximizing your light potential
reflectors
light movers
air cooling
which grow light is right for me?
LIGHT REQUIREMENTS FOR THE MAJOR STAGES OF PLANT GROWTH
coverage/energy Calculator
120 vOLT VS 240 VOLT

cOMPARISION CHART- BULBS

INTRODUCTION to LIGHT
Light is the most important factor in any indoor growing environment. It is also the limiting factor in any indoor growing environment. Without good and plentiful light, a plant will not be able to perform photosynthesis, the nitty-gritty process that occurs when a plant converts food into energy. Fortunately, plants are able to use artificial light, as long as there is plenty of it and it is of the correct growing spectrum.

Spectrums
Plants are under the spell of the seasons, and subject to seasonal changes in light. The blue end of the spectrum is associated with spring and lengthening days, promoting vegetative growth and short stocky stature. The red end of the spectrum is reminiscent of autumn, with shortening days and long harvest sunsets. Autumn usually promotes plants to finish up, creating flowers and seeds. It also gives plants a sweet, poetic feeling, like one gets upon seeing a beautiful sunset. We are not making this spectrum stuff up. Ask any plant.

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PhotoSynthesis
Of the many light-absorbing pigments within a plant’s leaf structure, the most active of is chlorophyll. Chlorophyll absorbs light from the blue and red wavelengths of the visual spectrum, turning plants into that stunning green our eyes have come to know and love. The absorbed radiant energy is used to convert ingested carbon dioxide, water and nutrients, to make carbohydrates which nourish the plants and promote new cell growth. This allows for strong, vigorous tissue production and the release of the oxygen. Correct lighting will result in healthy, happy, plants that are resistant to infections or colonizing hordes of insectoid pests.

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HID GROW LIGHTS
High-Intensity Discharge lights come as close to natural light as technology allows. However, they’re not so sophisticated as to completely reproduce the full spectrum. Consequently, two types of HIDs have been created to blend into a cohesive spectrum -- the Metal Halide and the High Pressure Sodium. These lamps produce four to six times as many lumens as any incandescent light of the same wattage-- and they last much longer. As close to natural sunlight as possible and even safer than a star? We guarantee these lights will never burst into a supernova or collapse in on their own gravity becoming a black hole and destroying the earth. Nope. Never ever.

An HID lighting system includes a ballast that runs a light socket, powering a bulb. A reflective hood sits around the bulb and focuses light onto plants that would otherwise be lost. Reflectors are either painted white inside or plated with a highly reflective aluminum or brilliant chrome. Some reflectors allow for air cooling, which exhausts hot air out from the bulb and out of the room.

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Digital Lighting
Electronic (Digital) Ballasts are ushering in the new age of indoor grow lighting, proving equal or increased light compared to the conventional core and coil Magnetic ballasts. Digintal ballasts do this at a more afforadable cost (due to their greater efficiency and less power usage.) Digital Ballasts offer less heat production and virtually silent opperation. They are also much lighter and smaller than their archaic hulking brethren. There are many different Digital Ballasts to choose from on the market today. All come from China (not a single Digital Ballast is made in the U.S. or any other country for that matter,) and most are faulty or poorly crafted. Stay far away from the FutureBrites or the Global GreenHouses (or any other Digital ballast with a fan - the good ones are at least Resin Sealed).

digital ballasts
We think the Lumateks are easily the best Digital Ballast on the market today. They are resin sealed, and produce the least amount of EMI (electro- magnetic interference) of any electronic ballast and conform to all international Electro-magnetic emission standards. What makes them really special is that they are 15-20% brighter than Standard Magnetic Ballasts and also most Digital Ballasts as well. Next to the Lumateks, nothing else really compares, but we had to choose another ballast it would be the Galaxy.

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HID BULBS
Many bulbs on the market are not suitable for high yield rooms. Incandescent lighting (ordinary light bulbs, spot lights, "plants lights" etc.) shouldn't really be considered. They are inefficient, not bright enough and have an incorrect color spectrum. If you want to grow plants using artificial light, HID grow lights are the best way to go.

There is one rule to follow when using HID bulbs. That is that HPS bulbs must be used with HPS lights and MH bulbs must be used with MH lights. there are numerous ways of getting around that rule and getting the kind of light you need from your fixture.

What are CONVERSION BULBS? How do they work?
Conversion bulbs are designed to allow MH systems to produce HPS light and HPS systems to produce MH light. This type of bulb allows the tailoring of the light source to the growth stage of the plant (again, using MH blue light for growth and HPS red light for flowering/budding) merely by changing bulbs.

Enhanced Spectrum Bulbs
Enhanced Spectrum bulbs produce a richer and more complete spectrum of light that is more accessible by plants. An enhanced spectrum HPS bulb (like the Lucalux - PSL or the Hortilux) is one that puts off more Blue light when compared to a standard High Pressure Sodium, which only emits Red and Orange light. An enhanced spectrum Metal Halidebulb puts either more Red or Orange light when compared to a standard MH (as in the SunMaster Warm Deluxe) or conversely a deeper richer spectrum of Blue light (for example, the SunMaster Cool Deluxe or the Hortilux Blue. Enhanced bulbs will either promote more Fruit and more Flowers, help with the overall vitality of the plant, or it keep the internodes tighter, and the leaves larger and greener.

Full Spectrum “Dual Arc Tube” Bulbs
There is a new kind of bulb that has hit the market which contains two arc tubes within it. It is, in essence, two bulbs in one. The Hortiux Super Blue contains both a 600w High Pressure Sodium arc tube and a 400w Metal Halide arc tube within its glass housing. This creates a true “Full Spectrum” canopy of light for plants to bathe and grow in. The light produced by these bulbs is lower in overall lumens created but very highly absorbable to plants.

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Caring for HID Bulbs
HID bulbs can explode if it is not handled correctly. This will occur if the bulb is very cold when first turned on, or if it contains fingerprint oils or moisture. To prevent accidents, never pick the bulb up directly by the glass - you need to be careful about fingerprints getting on it.. Handle the bulb by the base and wrap the glass body in a paper towel. Handling the bulb through the paper towel, screw it carefully into the lamp body.

If you need to clean the bulb, use a towel lightly dampened with window glass cleaner or rubbing alcohol; wipe all fingerprints, dust and impurities from bulb's glass surface. Let dry thoroughly before installing. After cleaning, always handle the glass through a paper towel. Also, make sure bulb is warmed up to room temperature before installing.

When MH bulbs are turned off they should be left to cool for 20 minutes before re-starting. Turning a Metal Halide bulb on when it is already hot severely shortens the life of the bulb and it can affect the intensity of the light. Metal Halides should be replaced after a year of heavy use.

High Pressure Sodium bulbs can be restarted after only 2 or 3 minutes after being turned off, and they should be replaced every two to three years.

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A Note About Lumens
The brightness, or amount of light particles emitted from a bulb, is measured in lumens or foot candles . Lumens are the total number of light particles coming from the bulb itself, and foot candles refers to the amount of light falling on a given area. As you move farther away from a light, the lumens stay the same, but the foot candles decrease. Natural sunlight and artificial light falling on a plant are measured in foot-candles (f.c.) while the light emitted by sources such as the sun and electric bulbs are rated in lumens.

There is controversy over the use of lumens as a measure for plant lighting efficiency. This is because lumens take into account human light sensitivity as opposed to plant sensitivity. Many growers feel that other units such as micromoles or par value (photosynthetically active radiation) might be more accurate and helpful units of measurement when referring to greenhouse crops and the plant lights used to grow them.

Light particles
Inexperienced growers often make the mistake of cramming too many plants under insufficient light. Without enough light particles to go around, plants will not have enough energy to grow. Plant growth will be spindly and weak and the grower will be sad, disappointed and confused. To avoid this happening to you, we suggest the use of a light meter to learn exactly how much light your plants are receiving. A light meter uses a photo-sensitive cell that creates an electric current when light particles fall on it and displays it in foot candles. From there, you can figure out if plants are getting the optimum amounts of light they need. Different plants require different amounts of light. Lettuce and herbs will need far less light than peppers or tomatoes, which must flower to produce their fruit. Plants that require hot sunny days to grow well will need quite a lot of artificial light to produce satisfactory results indoors - don’t starve them!

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Metal Halide(MH)
These lamps bathe plants in light from the blue end of the spectrum. They are commonly used in the early vegetative stages of blooming plants’ growth to create a strong plant which has large leaves and a thick stems to feed the fruit. One of the major benefits of MH lamps is that they promote tight internodal spacing between branches, keeping plants from stretching. MH light is used for plants that are expected to grow many leaves and become bushy, such as lettuce, spinach, cabbage and herbsRecent strides in lighting technology have begun to produce MH bulbs that will reproduce a deeper more balanced “Blue” spectrum . The Hortilux Blue is an amazing “Full Spectrum” bulb with a CRI rating of 90+. The SunMaster Cool Deluxe is a cheaper alternative to the Hortilux Blue, which although it does not put out as intense light, it does produce tight internodal spacing and deep green leaves.

High Pressure Sodium (HPS)
HPS bulbs reproduce light from the red/orange end of the spectrum. Plants use this light in reproductive processes, which means that HPS bulbs help your plants to produce more fruits and flowers. Exposing plants solely to a red spectrum light tends to make them stretch, lose their color and start to look downright unnatural. New HPS bulbs are available to include blue light to promote better vegetative growth. Our personal favorite is the Hortilux. If you’re only going to use one lamp, we recommend an balanced spectrum HPS, especially for plants that flower.

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Fluorescents
For most of plant growing history, fluorescents have best been used during early plant stages - when using a larger wattage light would be a bit like frying an egg on the sidewalk. They are mainly used to sprout seedlings and initiate rooting in cuttings. They cover a wide spectrum, but until recently they were not capalbe of growing healthy plants full term.

All that has changed with the new high output fluorescent lights that have just hit the market. These lamps have extremely high lumen per watt ratings and can be used for full term lighting in place of HID lights. The advantages of these lights are that they are very low in heat production and can be hung very close to the plant canopy, thus raising light levels. They are great for growing healthy powerful plants ready to take off into bloom!

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HIGH OUTPUT (T5) FLUORESCENTS
High Output (T5) Fluorescents are relatively new to this industry. They put off twice the amount of light when compared to normal (T12) Fluorescents for the same electrical costs. An example would be a standard, two-foot T12 fluorescent bulb, which gives off 1000 lumens compared to a T5 two-foot bulb which gives off 2000 lumens - both use the same wattage. High Output Fluorescents, like Compact fluorescents do really well Vegetatively growing plants or keeping Parent plants healthy. They can spread the light out over a square area (as in the the two-foot, 8 bulb fixture, taking up 2 ft. x 2 ft. of space) or over rectangular areas (as in the four-foot. 4 bulb or the four-foott. 8 bulb light fixtures) very well. High output Fluorescents put off very little heat compared to the great amount of light that they produce. As with Compact Fluorescents, these lights are not recommended for Fruiting or Flowering. These T5’s need to be run in specific fixtures with special electronic ballasts that can power their output such as the New Wave, Tek Light, SunBlaze, or Hydrofarm Commercial units.

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COMPACT FLUORESCENTS
Along with T5 lights, Compact Fluorescents are great at providing a good light with very little heat. They are also affordable when compared to HID lights providing the same amount of light. What makes Compact Fluorescents great for some applications is that the light emits from a single source as opposed to long banks of light like those found in normal (T12) fluorescents or those found in High Output (T5) Fluorescent banks. These work well in creating a square of light for plants to bask and grow in. A 100-125 watt Compact Fluorescent is good for a 1x1 to 1.5x1.5 Grow Space which can either house Vegetative Plants or Parent Plants (from which a grower can take cuttings from). A 250 watt Compact Fluorescent can provide enough light for a 2x2 Grow Space housing either Parents or Vegetative Plants. In our experience these bulbs do NOT do well with Blooming - Fruit / Flowering Plants.

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WORKING with INDOOR GROW LIGHTS
Different types of plants require different amounts of light. Lettuce and herbs will need far less light than peppers or tomatoes which must flower to produce their fruit. Some plants grow in the winter and flower in the summer. Most plants grow during the longer days of spring and early summer, and flower as the days shorten in late summer, fall, and early winter. These schedules can be easily simulated in an indoor environment.

Lighting cycles
One of the most important jobs of the indoor grower is reproducing the daily and seasonal flow of light. For vegetative growth, in addition to a bluer spectrum, plants are exposed to long growing days such as they might experience in spring and early summer . Plants that are meant to produce veggies, fruits or flowers are encouraged to begin the budding process by a change in the light cycle, and optimally a change of spectrum. In general, 18 hours of light is best for vegetative growth and 12 hours of light is the best stimulus for flowering (although, some plants do work on the exact opposite schedule).

Just about all plants need a regular period of light and a regular period of dark. During the light stage they absorb energy. In the dark period they build organic molecules from the energy they have absorbed. As you reproduce the cycle of nature, consistency is very, very important. Plants love a dependable pattern and will get stressed if the pattern becomes erratic. A good timer should be used in order to create regular lighting intervals of Lights On / Lights Off. The periods can be scheduled conveniently, as long as plants receive their light and dark at the same time every day. The general range is 6-12 hours of darkness every day. It is important not to disturb the dark periods, so be careful about visits that may add unwanted light to the room during that time.

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Maximizing Light Potential
Flat white walls are the easiest and cheapest way to reflect light back onto plants. A quick coat of paint can make a big difference to your crop.

If you'd like to protect the walls of your room and provide even better light reflection, you might want a roll of Black & White Plastic. Flat black on one side, the opposite side is bright white. It's easy to hang, is glossy, and doesn't crease easily. It's also easy to wipe down between crops.

A third and excellent option is Mylar which is shiny and provides an almost mirror-like surface to reflect light. It can be slightly difficult to work with and must be pulled tightly so as to provide a flat surface, and you will find it creates annoying crinkles which can diffuse and deflect light away from plant surfaces.

Plant Spacing
Inexperienced growers will often make the mistake of cramming too many plants under insufficient light. Without enough light particles to go around, plants will not have enough energy to grow. Growth under these conditions is far from optimal. Plants are weak and ill looking. The best way to prevent this do is to find out how much light plants are receiving using a light meter. A light meter uses a photo-sensitive cell that creates an electrical current when light particles fall on it and reads out in foot candles. From there you can figure out if plants are getting the optimum amount of light they need.

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Reflectors
Vertical reflectors hang the bulb vertically. This orientation causes the light to shine downward and outward in a circular pattern. They are available in either cone or parabolic shapes, both which offer very even dispersion of light. Plants are able to get a bit closer to the light with this type of reflector. Vertical reflectors hang from a single chain at their center point.

Horizontal reflectors lay the bulb horizontally. This orientation bounces light off the top of the reflector which shines downwards in a rectangular or box like pattern. There are different shapes and sizes of horizontal reflectors available. They are hung from two chains, one at each end of the reflector. Most horizontal reflectors need to be higher up above the plants compared to vertical reflectors.

Our Favorite Reflectors

Adjust - A - Wing
These reflectors are known to put out twice the power and efficiency of other reflectors on the market. They can increase the grow area up to 50% and increase the yield per lamp up to 75%. Adjust-A-Wings are made from a special glass-coated flexible aluminum and color bonded steel. When used with the super-spreader, which prevents any “hot spot” from forming directly under the bulb as well as spreading the light out more evenly, the Adjust-A-Wings become a powerful precision instrument.

YieldMaster 6” AC
This Completely sealed Air Cooled Reflector features gasketed glass and integrated restraint bars to hold glass tightly in place. It is made from 86% reflective German aluminum interior for excellent output and uniformity. This reflector is made to be a strong contender with fyll features and an affordable price. It features Very Good air cooling with built-in 6” fittings. Made with a powder coated finish. We feel this is a good entry level air cooled reflector or a strong budget unit for those purchasing alot at a time.

yieldmaster
lumenator 8" AC

Lumenator 8” AC
The Lumenator 8” AC Reflector is revolutionary at both spreading the light in a 4x4 square pattern, being a discounted reflector and giving maximum 8” air cooling. It employs a Highly reflective interior (which is made with German Aluminum and Hammered out for maximum light distribution) with material on all 4 sides. The Glass seals up nicely and the socket cord comes out through the top of the reflector. The 8” AC fittings that are built insure that long runs of ducting can be used to great avail.

Magnum XXXL 6” and 8” AC
The largest reflectors in the industry! The Magnum XXXL is Completely sealed - featuring gasketed glass and integrated retention bars to hold glass tightly in place. 95% reflective German aluminum interior offers excellent reflectivity and diffusion. It has a Powder-coated galvanized steel body and features Maximum air cooling with built-in 6" or 8” fittings. The Magnum 6” is 32 1/2" long x 26 1/4" wide x 7 3/4" tall. The Magnum 8” is 38½ in. Long x 29½ in. Wide x 9½ in. Tall. This is our Favorite Air Cooled Reflector by far!

Magnum XXL AC

Spartan AC Reflector
This is also one of our favorite reflectors. It is has German reflective material on All four sides and has many bends throughout the entire horizontal slope of the reflector which makes sure that a very even spread of light coverage results. This reflector also has a mirrored finish at the roof of the interior (directly over the bulb) which cuts the light in half and throws it over the entire body of the refltor and down on the waiting plants below. Again, if you are on a budget this is the reflector for you!

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LIGHT MOVERS
There are many benefits to using a light mover. First, it can provide the most optimal lighting possible by combining the spectrum of metal halide and high pressure sodium lamps. Second, a mover spreads light around so that fewer lights are needed, lowering electric costs. A third benefit to using light movers is that moving lights eliminate the problem of heat buildup and plants can get quite close to the light source without burning their leaves. Moving lights in a garden also eliminates the tendency of plants to grow toward a specific light source and it allows light to reach areas that might otherwise be shaded. A more democratic method for sure; equal light for all!

There are two main types of light movers: those that move lights in a circular pattern and those that move them back and forth in a straight line. The circular style is best when the width of your grow area is similar to the length. Light movers are capable of carrying a single lamp, but two or three is even better, as this option will supply the most light and plants can be placed closer together. The Light Rail is a linear light mover capable of carrying multiple lamps in a back-and-forth pattern. It has a six foot track which may be extended to cover the entire length of your room.

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AIR COOLING
One of the biggest indoor gardening challenges is the heat from HID lighting. This heat may be quickly and efficiently removed by air cooling the lamp reflectors. Plants can handle temperature degrees upwards of 90 degrees Fahrenheit when in a CO2 enriched environment. (In fact heat is a very necessary part of the overall bio-chemical formula.) In such a situation, air cooling can often take the place of air conditioning. Air Cooling a Grow Light can drop the temperature in a Grow Space signifcantly, dropping temperatures up to 7 degrees. Below are two ways to cool one light, still bring fresh air into the space, and clean with a carbon filter.

one fan air cool design

One Fan Air Cool Design
This diagram above illustrates how one fan can effectively air cool a single light as well as bring fresh air through the grow space (in from a passive intake) and pass it through a carbon filter. The carbon filter will pull any odor out of the air before passing it through the light and out the grow space. When the fan turns on, it will exhaust air from the space, through the carbon filter and then through the hood, out into space. This creates a negative pressure (a vaccum) within the space itself which will pull fresh air in through the passive intake located below. While this design is good for those growers on a budget who want to only use one fan, it will not cool as effectively as the design below.

Two Fan Design
The air flow in this diagram is similar to the one above. Air enters the room through a passive intake below. The main difference is instead of one fan to cool the lights and exchange the air within the space, we now have two fans. One is dedicated to air cooling the lights with its own passive intake on the opposite end. The second fan is dedicated solely to exhausting the air within the space iteself.

Air Cooling with a Series of Lights
Air Cooling Grow Lights can drop the temperature in a Grow Space signifcantly, dropping temperatures up to 7 degrees. Below are two ways to cool multiple lights, still bring fresh air into the space, and clean with a carbon filter.

The illustration above indicates the ideal setup for air cooling multiple lights in a row. This design utlizes two fans; one on either end. This provides for maximum pushing / pulling power. (We like two 8” fans for cooling up to four lights.) The HEPA Filter, although an addtional cost, prevents dust from collecting within the reflector housing and on the glass. When using one of these handy little items, you will not have to clean the glass nearly as much! If you are going to be using multiple lanes of lights (the above illustration being one such lane) than you can hook them up with two fans per lane or use the Parallel Cooling design illustrated below.

 
Parallel Air Cool Design - Cooling for Two Lanes of Lights
The illustration above indicates how two fans can be used (with the help of two Y Connectors - one on either end) to effectively air cool a given set of lights. This design only shows four lights (two per lane) but there is not reason that it cannot cool 2-3 times this amount as long as the fan or fans are strong enough. It is also possible to use this parallel design with only one fan (at either end) to cool; it would just have to be a Strong Fan.
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Which Grow Light is Right for Me?
This is an age-old question that we feel needs some special attention. Of course no one can fully answer how many lights is right for any one grower. But, what we can offer is some useful information that will help you come to a descision that is right for you. The more light you add into a grow space, the more fruit / flowers you will produce. Light is directly proportional to yield (up to a point of full saturation). You cannot produce more light than what the sun would produce on its brightest day. So how do we decide what too much light is? Or how much light is enough for a given grow space? Below, we have gathered information that you can utilize to make your descision.

A 1000w light will blanket a 4x4 area with light; even up to a 5 x5 or larger depending on the reflector and the stage of growth a plant is in. A 600w ligh can cover anywhere between a 3x3 and 4x4 area of light depending on the reflector and the stage of growth a plant is in. A 400w light can spread up to a 3x3 area (even a 4x4 for plants in Veg. growth), but works well in a 2x2 area for plants in the bloom stage with higher foot candle / lux requirements. A 250w light will cover up to a 2x2 area. From these simple measurments one can effectively decide how many lights are needed to light up any given grow space. For a more exact coverage area, come talk to us about the different reflectors we stock and how they can be best applied to your given grow space. We are here to help and more than happy to answer any of your questions or elp with the design and fulfillment of your given grow space requirements.

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LIGHT REQUIREMENTS FOR THE MAJOR STAGES OF PLANT GROWTH
Different light levels are required for the different stages of plant growth. A general rule of thumb has it so that 1/4-1/3 of the wattage you are using for the Bloom Stage is necessary for use in the Vegetative Stage of Plant Growth. An example would be 41000w lights are to be used in the Bloom Stage - Anywhere from 2 400w lights to 3 600w lights can be employed for the VegetativeStage. Beyond this, it also about spreading the available light as evenly as possible. This depends on the incorporation of the above layout diagram as well as the use of a good reflector. Please see our “info sheet” on Reflectors for more information on how to pick the best reflector for you. Below are foot candle/lux measurements which can be used to help dial in your plans.

  • One Foot Candle = 10.76Lux
  • Vegetative Growth Stage - 2,500-5,000 FC --- 25,000 - 50,000 lux
  • Bloom (Fruiting / Flowering) Stage - 5,000- 6,500 FC --- 50,000 - 70,000 lux
  • Ripening Stage - 3500 - 4500 --- 35,000 - 45,000 lux
We like using 55-60,000 lux or 5500 Foot Candles for optimum growth in the main part (usually weeks 1-6 of the Bloom (Fruit / Flower) Stage.

Max Sunlight on earth’s surface is 90,000 lux and is not good for plant growth. Generally speaking over 70,000 lumens and you are beyond the optimum level of light for photosynthesis to occur. Don’t become a grower who just doesn’t believe and over does their lighting. Just becuase it is cool doesn’t mean it is not too intensely lit.

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Coverage/Energy Calculator
What is the plant area is that you need to cover? Multiply length x width to get square footage. For optimum lumens, you need between 20 (min) and 60 (max) watts per sq ft. For example: if you have a 4’ x 4’ area, which equals 16 sq ft, multiplied by 30 watts you get 480 watts. That means you need at least a 400 watt light; but would do much better with a 600 watt or 1000 watt Grow Light. Keep in mind, the actual amount of light you'll need depends on the requirements of the type of plants you are growing. Some plants like more light, some like less. There may be several different arrangements that will give you optimum light energy. For example: for 2400 watts, you could use (2) 1000 watt lights and a 400 or (4) 600 watt lights, etc. We will be happy to give you a suggestion.

We've created a Lighting Calculator to help you determine the correct number of lights for your room. It will tell you the wattage per square foot of various lighting configurations of your choosing. Play with it to decide what sort of lighting arrangement you'll need.

For optimum lumens, you'll need between 20 (minimum) and 60 (maximum) watts per square foot. There may be several different arrangements that will provide the optimum light energy. For example if you needed 2400 watts, you could fill that with two 1000 watt lights and a 400 or with four 600 watt lights, etc.

Calculating your Electric Costs
You need to first find out how many watts you will run. Next you must calculate your kilowatts per hour (KWH), which is located on your last electric bill.
Note: 1 KW= 1000 Watts

Watts of light = Amount of Kilowatts you are running per hour
Example: 2000 Watts = two 1000 watt lights
2000 Watts X 1000 watts/1 kw = 2 kw per hour of use
So now say you are running your lights for 12 hours a day. You then multiply your kw per hour by 12 (hours running in the day)
So in our previous example: 2 kw/ hour X 12 hours = 24 kilowatts a day
Multiply by days in a month: 24 Kw per day X 30 days = 720 Kw per month
Now you take that figure and multiply it by the rate charged by the electric company.

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What is the difference between 120 volt and 240 volt?
Both 120 volt and 240 volt lights operate with the same 100% output and use roughly the same amount of electricity. A 600 watt light uses the same amount of current in 120 volt as in a 240 volt light. The standard outlet you see in your house is 120 volt. You may want to get a 240 volt if you plan on running several lights off of one circuit breaker. The maximum wattage on a 120 volt circuit is 1500 watts, per National Electric Code. With proper wiring, 240 volt circuits can carry up to 5760 watts. This means that you can plug several high powered lights into a lighting timer that will turn them all on and off on the same circuit. 240 volt is also considered to be more 'stable' because it uses half the amps. The equation: Amps x Volts = Watts. There is some savings using 240 Volt - Because there is less Amperage, there is less heat and less conductance. This begins to add up as more power is consumed.

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COMPARISON OF BULBS

NAME/
DESCRIPTION
WATTAGE/
LUMENS
SPECTRUM
NOTEWORTHY REMARKS

HPS Bulb
HPS BULB

400W 50,000 600W 85,000 1000W 140,000 APROX. 2000K
WARRANTY: 1YR. WARRANTY. REPLACE AFTER 9 MONTHS- 15% LESS LUMENS.
NOTES: THESE ARE STANDARD IN EVERY WAY. THEY GET THE JOB DONE. THEY ARE CHEAP AND MAKE FOR A GOOD FIRST BULB. NO BLUE SPECTRUM.
Metal Halide Bulb
MH BULB
STANDARD
400W 36,000 1000W 110,000 3500K-4000K
WARRANTY: 1 YR. WARRANTY. REPLACE AFTER 9 MONTHS- 15% LESS LUMENS.
NOTES: DOES THE JOB. AGAIN, VERY STANDARD. BETTER FOR VEG. THAN EVEN AN ENHANCED SPECTRUM HPS. DOES NOT COMPARE TO "BLUE" BULB
EYE Hortilux Bulb
HPS BULB
HORTILUX ENHANCED
400W 55,000 600W 88,000 1000W 145,000 2300K
WARRANTY: 1YR. WARRANTY. REPLACE AFTER 9 MONTHS- 15% LESS LUMENS.
NOTES: INDUSTRY STANDARD ENHANCED SPECTRUM BULB. 30% MORE BLUE LIGHT. EXPENSIVE. 1000W- INDUSTRY ONLY ENHANCED SPECTRUM.
PSL Lucalux Bulb
HPS BULB
LUCALUX PSL ENHANCED
400W 55,000 600W 90,000 2300K
WARRANTY: 1 YR. WARRANTY. REPLACE AFTER 9 MONTHS - 15% LESS LUMENS.
NOTES: THE PSL BULB IS OUR NEW BULB OF CHOICE. ONLY COMES IN 600W AND 400W. 30% MORE BLUE LIGHT. MORE LUMENS THAN HORTILUX

MH BULB
HORTILUX BLUE FULL SPECTRUM
400W 29,000 1000W 80,000 6500K
92 CRI
WARRANTY: 1 YR. WARRANTY. REPLACE AFTER 9 MONTHS - 15% LESS LUMENS.
NOTES: THE HORTILUX BLUE HAS A VERY COMPLETE SPECTRUM. THE ONLY OTHER BULB THAT COMPARES IS THE SUPER BLUE DUAL - ARC.
SunMaster Cool Deluxe
MH BULB
SUNMASTER COOL DELUXE
400W 30,000 600W 50,000 1000W 80,000 5000K
WARRANTY: 1 YR. WARRANTY. REPLACE AFTER 9 MONTHS - 15% LESS LUMENS.
NOTES: THE ONLY GOOD 600W GROW BULB (CONVERSION). BLUE BURNING. THEY WILL CREATE DEEPER GREEN LEAVES & SHORTER INTERNODES.

CONVERSION HORTILUX MH>HPS
360W 45,000 940W 130,000 2100K

WARRANTY: 1 YR. WARRANTY. REPLACE AFTER 9 MONTHS - 15% LESS LUMENS.
NOTES: THESE CONVERSION BULBS ALLOW A METAL HALIDE BALLAST TO PUT OFF A WARM (ORANGE/RED) HPS SPECTRUM.

Hortilux Dual Arc Bulb
DUAL ARC BULB
HORTILUX HPS AND MH
1000W 110,000 3000K
WARRANTY: 1 YR. WARRANTY. REPLACE AFTER 9 MONTHS - 15% LESS LUMENS.
NOTES: ALTHOUGH RATHER SPENDY - THESE BULBS ARE THE WAVE OF THE FUTURE. TWO ARE TUBES. BOTH HPS AND MH SPECTRUMS.
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