Beginners Guide To Choosing Perfect Grow Lights

Hydro 101: An 8-step guide to successful indoor gardening

1) Environment

Having the right environment is critical for your garden. Key elements to a successful garden room include relative humidity, temperature, CO2 (Carbon Dioxide) and air circulation/exchange. The ideal humidity for a garden room falls between 40 & 60 percent. Some plants like higher humidity, but know that higher humidity can lead to problems with fungus and disease. Temperatures in your grow room should be between 68 – 75 F degrees. Temperature changes will lead to variations in humidity levels. Avoid drastic temperature changes over a short period of time. Your plants need CO2 to grow. Assuming you have good air circulation/ exchange, your garden room will naturally have between 300-400 PPM (parts per million) of CO2; higher CO2 levels should accelerate growth rates. If you choose not to supplement CO2 in your garden room, it is important to address the air circulation/exchange so that your plants will receive fresh CO2.

2) Best water possible

The water you use for your plants will determine how well your plants will grow, regardless of what you add in terms of nutrients and supplements.PPM (parts per million) or EC (electrical conductivity) are the measurement of the salts in a solution. Neither PPM nor EC readings will tell you what is in your solution / water, but rather are indicators of the solutions ability to conduct electricity. Ideally, you want to start of with a low PPM or EC then you can add nutrients specified to your plants requirements. You can reduce the PPM of your water using a Reverse Osmosis (R.O.) unit then build your nutrient solution around what your plants need. pH (potential hydrogen) measures the acidity or alkalinity of your solution on a scale of 0 – 14. A solution is considered acidic below 7 and basic at 7 or higher. When working with hydroponics you typically want your pH to fall between 5.8 and6.2. When growing in soil or coco you want your pH between 6.0 and 6.8. The most important rule to remember with pH is to avoid extremes. Nutrient “lockout” occurs with high and low pH levels.

3) Method

Ebb & Flow gardens flood and drain a tray of plants with a nutrient solution at regular intervals. A drip garden provides nutrient solution to the plant through tubes & emitters (drip stakes) to each plant. Aeroponic growing mists an oxygenated nutrient solution directly to the roots of a plant. NFT (Nutrient Film Technique) gardens create a slow moving nutrient solution -‘film’- that flows over the roots of the plants. Organics have become a preferred method of growing. Choose the size container you want, an organic soil/medium, an organic fertilizer and water by hand.

4) What medium?

Growing mediums act as the anchor for the plants root system. Some add nutritional value to your plants while others simply give the roots something to hold on to. Some mediums to consider are soil, soil-less mixes, coco, hydroton, rockwool / stonewool, or silica stone. Coco is available in both a loose and compressed form. Coco is made from the husks of a coconut, and it is very pH stable and provides good moisture retention and natural aeration qualities. Hydroton or clay pebbles are made from expanded, pH neutral clay. They tend to hold water well and have great oxygen to water ratio; this makes hydroton suitable for hydroponic and soil gardens. With proper sterilization techniques, hydroton can be reused. Rockwool is made from stone that is heated then spun into fibers. It is then compressed into starter cubes, grow blocks, or slabs. This medium has excellent oxygen to water ratio. Rockwool tends to have a higher pH, so flushing with 5.5-5.8 pH balanced water or a rockwool conditioning solution is recommended. Rockwool works best in an ebb & flow and drip systems. Silica stone is a rock that contains high levels of silicate which helps slow transpiration rates of plants. This is especially helpful in garden rooms that have temperatures above 85 F degrees. Silica stone is pH neutral and environmentally friendly. Like hydroton, silica stone can be reused and is suitable for hydroponic and soil gardens.

5) Nutrients

Like humans, plants require food (nutrients) to grow. Nutrients come in organic and synthetic varieties and are available in both liquid and dry form. Nutrients can be separated into two categories, macro and micro nutrients. The macro-nutrients are nitrogen, phosphorus, potassium, calcium, magnesium and sulfur. The micro-nutrients or trace nutrients include iron, manganese, boron, zinc, copper, molybdenum and chlorine. If the nutrients are deficient or are abundant you may see burning, curling or yellowing. You do not want to over or under fertilize. There are many different types of nutrients/fertilizers available on the market. You can purchase organic, synthetic (chemical) or a combination of both. Most nutrients/fertilizers will have an N-P-K (Nitrogen, Phosphorus, and Potassium) on the front of the bottle. In the vegetative or growth stage the “N” will typically be higher. In the flowering or bloom stage the “P” will typically be higher. You may also consider implementing additives/supplements into your nutrient mix. Additives/supplements can bolster microbial activity at the root zone, increase size, flavor and aroma. When used together, nutrients and supplements will help you achieve maximum results.

6) Lighting

LED Lighting is becoming the preferred lighting in a garden room. The three LED brands we used are Kessil, HydroGrowLED, AquaticLife, and more. Another type of lighting ideal for plant growth is T5 lighting. T5 lighting is a high-output fluorescent light with low heat and minimal energy consumption. It is an ideal light for cuttings, mother plants and short growth cycles. All plants require light in order to grow and bloom. Most plants grow and bloom according to the amount of light they are given. In the growth or vegetative stage plants typically want 15-18 hours of light. In the bloom stage you reduce the amount of light your plants get to 10-12 hours. You want to make sure the light comes on and of at the same time everyday (just like mother- nature). The best way to accomplish this is by putting your light on a timer. Please consult your nearest hydroponic retail store for more information on which light is best for you.

7) Controllers and Timers

There are many different meters available for testing pH, PPM, EC, temperature, humidity, CO2 and light levels. Single meters are available as are combination meters that test and/or monitor your environmental conditions The important thing to remember is your garden will only be as good as the limiting factor. Water, nutrient, light, temperature, humidity, CO2 & circulation are the elements to a successful garden room. By “dialing in” these elements, you will ensure a successful and bountiful garden.

8) Accessories

There are many items available to help your garden grow. Organics, controls, fans, blowers, plant stakes, relays, nutritional supplements and the lists go on. Consult with your retail supplier to discuss what the best accessories for your garden are. Happy Gardening!!

FAQ – Horticultural Lighting

General lighting questions:

  1. What is HID Lighting?HID lighting stands for High Intensity Discharge, which is a special type of lighting that is much more intense (brighter) than other types of lighting available. An HID lighting system consists of a ballast, reflector, socket and lamp (light bulb). The ballast acts like the engine, converting and driving energy to illuminate the lamp. HID lighting options include High Pressure Sodium (HPS), Metal Halide (MH), Mercury Vapor and Low Pressure Sodium. The two typically used for plant growth are HPS and MH systems.
  2. What is Color Rendering Index (CRI), Color Temperature (K) and Lumen?Color Rendering Index is a subjective measurement of how well a lamp source renders colors. A measurement of the degree of color- shift an object undergoes when illuminated by a light source when compared to a reference source of comparable color temperature. Incandescent light is assumed to have a CRI of around 100 so it will render all colors correctly. MH only has a CRI of about 70, so only 70% of colors will be rendered correctly. HPS has a CRI of 22.Color Temperature is not how hot the lamp is. Color temperature is the relative whiteness of a piece of tungsten steel heated to that temperature in degrees Kelvin. HPS has a warm (red) color temperature of around 2700K as compared to MH at 4200K, which has a cool (blue) color temperature.

    What is important to remember about these two terms is that CRI readings, of two sources, can only be compared if their color temperature is equal. You cannot compare the CRI of HPS (CRI=22) vs. Metal Halide (CRI=70) because the color temperatures are different (2200K vs. 4500K).

    Lumen is a measurement of light output. It refers to the amount of light emitted by one candle that falls on one square foot of surface located at a distance of one foot from the candle. Traditionally, lumen has been the benchmark of a lamps ability to grow plants; meaning the brighter the lamp the better the plant. However, studies have shown that a broader color spectrum lamp will perform much better than a lamp with high lumen output, especially when it comes to plant growth.

  3. What is the difference between MH and HPS with regards to plant growth?MH lamps provide more of the blue/green spectrum, which is ideal for leafy crops, and/or plants that are in a vegetative (actively growing) stage. MH lamps provide a more natural appearance in color and are typically the choice for plants that have little to no natural light available. HPS lamps provide more yellow/orange/red spectrum, which is ideal for most plants that are actively fruiting and flowering. In addition, HPS lighting is the choice for growers looking to supplement natural sunlight. Ideally, the horticulturalist will use MH to grow their plants and HPS to fruit and flower their plants.
  4. What is the difference between HID and Fluorescent lighting with regards to plant growth?Traditionally, fluorescent lighting was used for seedlings, cuttings and plants with low light-level requirements and HID was used for established plants and plants with higher light-level requirements. Advances in fluorescent lighting technology, however, have provided more options for horticulturists. T5 fluorescent lighting is the latest in plant growth lighting. T5’s high-light output combined with its low heat and energy consumption makes it an ideal light source to grow a broader array of plants.
  5. What are the benefits of using T5 fluorescent lighting for plant growth?T5 lamps provide the ideal spectrum for plant growth. Photosynthesis rates peak at 435 nm and 680 nm. A 6500K T5 lamp has a spectral distribution with relative intensity peaks at 435 nm and 615 nm. This equates to very little wasted light energy in terms of plant growth. T5 lamps promote incredible health and vigor of seedlings and cuttings. Root development is superior relative to other lighting sources. While T5 lighting is excellent for starting seeds and cuttings, it’s also able to produce enough light for full term growth. Because of their minimal heat output, T5 lamps can be placed 6” – 8” above the plant canopy which maximizes photosynthetic response. Unlike conventional fluorescent lamps, plants grown under T5 lamps do not have to be rotated to the center of the lamp. T5’s slim diameter enables better photo-optic control of the emitted light, increasing efficiency in the form of even light distribution.Environmental Impacts of T5 (at a glance):
    • T5 lamps have a diameter of 5/8” – smaller is better when it comes to manufacturing, transportation and disposal.
    • Reduction in raw materials and components needed for manufacturing.
    • Reduction in lamp and fixture packaging materials due to relative size.
    • T5 are constructed of 40% less glass than T8.
    • T5 contain 30% less phosphor than T8.
    • T5 contain 3mg of mercury. 70% less than T8.
    • Longer lamp life means reduced maintenance cost and less going to the landfill.
  6. What are the major differences between HID ballasts and electronic ballasts?Frequency output to the lamp and energy conversion from electricity to usable light are the biggest differences between HID ballasts and electronic ballasts. HID ballasts produce a frequency of 60 Hz. Electronic ballasts vary from manufacturer to manufacturer, but the frequency produced can be 400x that of an HID ballast. HID ballasts produce more heat than electronic ballasts, thus making electronic ballasts more energy efficient. You will not, however, save money on your electric bill by using electronic ballasts. HID lighting has been available for 60+ years, while electronic ballast (especially 400 watt and higher) is a relatively new technology.
  7. Are electronic ballasts more energy efficient?Electronic ballasts are more efficient at converting electricity into usable light. Since your power bill is based on kilowatt-hours and not efficiency, a 1000 watt electronic ballast will cost you about the same as a 1000 watt HID ballast to operate.
  8. How much energy will my light use?An average lighting system will increase your electricity cost about $8 to $20 per month. The exact amount depends on the wattage of the system and the number of hours operated. To calculate your cost, multiply the bulb wattage X the number of hours of operation and divide by 1000. This figure is the number of kilowatt-hours of electricity used. (Example: a 400 watt lamp running for 18 hours will use 7.2 kilowatt-hours). Check your power bill for the cost of each kilowatt-hour. Then multiply the number of kilowatt-hours used by the cost of a kilowatt-hour (K/hr) to figure the cost to run your light for that many hours.
  9. Do I need special wiring in my house for my lighting system?Lighting systems are available in a variety of voltages. The standard used by most gardeners is 120 volts / 60 Hz which plugs into a standard wall outlet. Other voltages may require special circuits and receptacles. Always contact a licensed electrician if the light you purchased has special voltage requirements and never exceed more than 75% of the rated ability of the fuse/breaker. (For example: use no more than 15 amps on a 20-amp circuit.)
  10. What voltages are available for HID and Fluorescent lights?HID systems are available in 120 volt, 208 volt, 240 volt, 277 volt and 480 volt – All at 60 Hz. Fluorescent lighting varies, but most are available from 100 volt to 277 volt and 50 Hz or 60 Hz.
  11. Will I save on my electric bill if I run my system with 240 volts?No. Electric companies base your electrical bill on Wattage, not Voltage or Current. While ballasts wired for 240 volt will draw less current and run a little cooler than one wired for 120 volt, it will not save you money on your electric bill.
  12. How often do I need to change my light bulb?Most lamp manufacturers rate their lamps by “Average Life Hours” and usually claim 10,000 to 24,000 hours. These ratings are based on when the lamp will completely fail to come on. They do not factor in loss of intensity or loss of color. HID lamps lose intensity and color through normal use. This is OK if you are lighting a warehouse, but when it comes to plant growth, these losses can mean wasted electricity and poor plant performance. Serious horticulturalists recommend that you replace your lamps after 6000 hours of use. This equates to using your light 16 hours a day for one year.
  13. How long should I run my lights?This depends on the type of plants and whether you have natural sunlight available to your garden. As a general rule, when you are in a vegetative stage of plant growth and you have no natural sunlight, run your lights 14-18 hours a day. If you have natural sunlight, it will vary because the sunlight may or may not be direct. It will take a little experimenting to find the best length of time to run your lights. If you are actively fruiting and flowering, the rule is to run your lights 12 hours a day if you have no natural light.
  14. How high do I need to hang my lights above my plants?The higher the wattage the further away you want the light to be from your plants due to the amount of heat. HID lighting will be further away than a fluorescent fixture because of this. When mounting your lighting fixture take into account the type of plant and how tall the plant will grow. You want to keep the light as close as you can, but not so close to burn the plant. A simple rule is “if it is comfortable for the back of your hand, it will be a safe distance for your plants”. Doing a little research on the type of plant and where it comes from will help in determining how much (or little) light your plants like. With fast growing plants, you may need to check the hanging height on a regular basis as plants that get too close to the lamp will be severely burned.
  15. How big of an area will my light cover?The size of the garden area will determine the wattage you need. If we assume that the plants will get no sunlight, a 1000 watt light will cover about 7 x 7 feet of growing area. A 600 watt will cover 6 x 6 feet, a 400 watt will cover 4 x 4 feet, and a 250 watt will cover 3 x 3 feet. These sized areas would be considered the “Primary Growing” areas. These lights will light-up larger areas, but plants placed outside of the Primary Growing area, will stretch and bend toward the light; a phenomenon called photo tropism. Keep these areas of coverage in mind when using multiple fixtures. The best results occur when the areas of coverage overlap.
  16. Why do I need glass to get the ETL Listing on a Metal Halide light?The inner arc tube of a Metal Halide lamp contains mercury. Eddison Testing Laboratories has stated that for a Metal Halide fixture to maintain its ETL Listing, that an additional tempered safety lens is required in the event that the arc-tube and outer glass fail. This will prevent the spread of Mercury.
  17. Can I run a 1000 watt bulb in my 400 watt lighting system?No! The internal components of the ballast are designed to send the correct voltage and current for the rated lamp. Mixing lamps and ballasts will result in premature failure and will void the manufacturers’ warranty. Consider the size area you want your garden to be prior to making a lighting purchase. It is better to grow into a fixture than out of one.
  18. Can I run a 430 watt bulb in a 400 watt lighting system?Yes, the internal components of 400 watt and 430 watt ballasts are almost identical. You will only get 400 watts of light out of the 430 watt lamp, however.
  19. Do I need to wear gloves when handling an HID light bulb?Manufacturers do not state that gloves are required when handling their lamps. It is recommended that your hands be thoroughly washed prior to handling HID lamps though.
  20. What is a conversion bulb?A lamp that operates on the opposite ballast it was originally designed for. For example, a 940 watt conversion lamp is an HPS lamp that runs on a 1000 watt Metal Halide Ballast. There are also MH lamps that are designed to operate on HPS ballasts. These bulbs allow the grower to purchase the ballast of their choice and offer the flexibility of growing a variety of plant types by simply changing the lamp they need.


What lighting kit should I use to grow 1 plant in a closet?

We recommend using LED lighting with a timer for a closet environment.  It uses significantly less power than its HID counterpart, and can be placed as close as 6 inches above your plant.  In this environment, we also recommend using flowering potting soil, and a large pot with a large capture disc underneath in case of over watering.  Be sure the pot has a hole at the bottom as the soil needs to be able to drain properly.  Too much water will kill a plant.  Lastly, Ventilation.  You’ll need a fan to circulate the air because closets (at least ours) do not have windows.  A simple house fan pointed into the closet will be fine.  You’ll need to monitor temperature (room temp is great) and pests.  Soil from anywhere has pests in it – lots of em.  This is always a problem for soil growing.  There are many ways to maintain pests, but we recommend exterminating pests in your soil (just like you would coral rock) before you plant.  This will make pest management much easier to deal with while growing.

What lighting kit should be used for 3 plants in a large closet?

LED is still probably your best bet for 3 plants in a larger closet environment.  Temperature and electricity being the heaviest decider.  However, if you are a metal halide and HPS fan, then you could consider a low watt Starter Kit from Apollo.  They are inexpensive and have everything you need to start growing but the flowering soil and the pots.  There are many ways to maintain pests, but we recommend exterminating pests in your soil (just like you would coral rock) before you plant.  This will make pest management much easier to deal with while growing.

What lighting kits are best for a basement setup on your own garden?

Here’s where there are some options.  You may need the heat produced by the HPS systems if you are in a colder environment, so despite the saving in electricity, you may be better off using HPS because of the heat it generates.  In this environment, you’d want to go with at least 1000 watt starter kit from Apollo Horticulture.  Ideally, you’d have a 2x1000W setup.  As for LED, the same benefits apply:  Low power consumption, and low heat.  If you have sufficient heat, then LED is also great (Kessil, HydroGrow, Aqua Illumination, Hamilton).  Again, ventilation and pest control will be key.  The main issue you’ll have is getting air circulation in a basement.  This is when people add CO2 systems to the equation. All plants need is light, CO2 and mineral water (We all wish is were that simple in practice), and it’s important to have the correct balance of each.  Temperature will depend on what plant/herb you are growing. There are many ways to maintain pests, but we recommend exterminating pests in your soil (just like you would coral rock) before you plant.  This will make pest management much easier to deal with while growing.

Is it worth it to buy led vs traditional lighting?

Over a three year period, if you just look at power consumption, absolutely.  The first year, you’ll be out some cash, but by year three, you’re in the green!  The highest yields come from LED and HID lighting.  Consider your climate before deciding.  HID creates heat (which some want and some don’t), and LED is low heat, low power consumption, but more expensive up front.

What is the the dummies definition of these lighting systems cfl / led / HID/ T5 / Retrofit etc?

CFL – Compact Flourecent Lamp:  CFLs are used all over – you may have one above you now!  There are many types of CFL lamps.  The technology began for a need for low energy lamps that last a long time and can light up rooms as well as other less efficient lamps/bulbs.  You’ll see them in retal stores, school classrooms, in your home (the swirl lamps), everywhere!  However, on HO (high output) CFLs are strong enough to mimic the sun’s spectrum.  CFLs come in T12, T10, and T8, but T5 HO has become the industry standard in CFL for both aquarium and horticulture.

How can I avoid fire hazards with my grow kit?

We all see it on the news, but how often does it happen.  The answer, not much. However, like anything else, being responsible, using common sense, and being safe will prevent a fire.  Keep all ballasts, bulbs and anything connected to a power source AWAY from minerals, water, or anything that could cause a short.  Do not place any equipment on carpet or wood.  Use a heat resistant surface for your ballast.  Use a surge protector and high quality timers.  Timers can short out, too.  If in a confined environment, remove ALL remotely flammable items out of the area.  Do not let the hood, reflector and/or bulb touch anything except the hanging kit.  Heat travels fast!  These are suggestions and are not the only things to prevent a fire.  Again, common sense.

How long should i keep my lighting kit on per day?

This is a question we get frequently.  It really depends on what you are growing and what stage you are in.  HPS is for flowering and MH is for growth.  If starting from a see and you want to maximize growth, keep metal halide on 24/7 for a month, then cut lighting time to 16h on and 8h off, until the pant reaches desired height.  Then you can swith the bulb to HPS and start the flowering process.  For LED, the time frame is the same, but the spectrum of light is complete, so not switching of lamps needed.

What is difference between 250 watt kit / 400 watt kit/ 600 watt kit/ 1000 watt kit?

POWER.  Some immediately say, the more the better!  Not necessarily.  The larger the area, or the larger the reef aquarium, the more wattage you’ll need.  Electronic dimmable ballasts are a great solution, because you can adjust the wattage, helping save space with multiple ballasts for one hood (for example).

Should I pad the walls around the lighting kit with anything to avoid fire hazard?

Padding the walls is not something to do UNLESS it’s with a fire retardant material.  You want to avoid any flammable material in your grow area.

How long does it take a plant to fully grow before it can be harvested with lighting kit?

It depends on the plant, but there is evidence that LED grow lights can produce a ripe tomato in 35 days.  However, harvesting other species of plants could take up to 3-4 months.

Should I use an irrigation system for my plant / plants? Or should i just water by hand?

Irrigation systems are a convenient way to help take some responsibility off your back.  However, irrigation systems require maintenance, too.  So, if it’s a large outdoor area, ABSOLUTELY use irrigation.  You can control the amount and frequency of the watering.  If indoor, it’s risky.  If the irrigation system clogs, it could ruin your crop and make a BIG mess.  There are many ways to maintain pests, but we recommend exterminating pests in your soil (just like you would coral rock) before you plant.  This will make pest management much easier to deal with while growing.

Should I use a power strip for my lighting system or plug directly into the wall?

High quality power strip with serge protection.  Don’t cut corners!

Should I trim my plants to increase production and does it speed up growing?

Grooming is very important.  Like a large tree that is growing dangerously close to your home, you want to manicure the plant to maximize where it expends its energy.  The more attention a plant gets the happier it will be, and the happier you’ll be with the finished product!

Is it faster to grow indoors then outdoors? Is quality better?

This is a matter of opinion.  Again, temperature, quality of light, quality of mineral water, and pest control are the main factors.  These areas are crucial to maximizing your yield.  Nothing beats the sun and perfect climate, however, you can control climate indoor, and you cannot control nature.  Indoor, your plants are safe, monitored and are a great conversation piece!

Where and when is it legal to grow medicinal marijuana?

Dedending on the state and, even down to the county level, you’ll need to consult the laws.  However, if it is legal in your area, there is no season you can’t grow, just limits on amount.  Again, check your local county and state for exact parameters.

How much MMJ can i grow?

Defending on the state, there are different allotments.

How can i get a medicinal card?

If your state offers MMJ cards, then you’ll need to see a MMJ doctor and describe your symptoms, and he or she will decide if you are in need of natural herbal medicine.

Can i grow and sell to medicinal dealers?

Yes, as long as you have a legal right to grow.  Check state laws regarding details.

What are penalties for growing over the legal amount?

There can be harsh penalties as this is a maturing market and law.  Do not push the limits of your amount.  This is why we recommend only the best lighting and equipment.  You want a speedy harvest to maximize yield.

When I order grow tools can i have it delivered as another type of product so people don’t know what I’m doing here?

We ship in a discrete brown box, and anytime you need special handling, just let us know!  We’ll make the extra effort.

How can I get free grow advice?

Visit Extreme Led Grow Lights