Basic info on fluorescent lighting

SmokeyMacPot

New Member
This is a compilation of basic information on fluorescent lighting that I have gathered over a period of several months.

What is a fluorescent light?
A fluorescent light is made up of a glass tube coated with phosphor, which is filled with a mixture of gases. When electrical current is applied, it "excites" the gases, causing the tube to glow brightly. ie: to "fluores".

Why do fluorescent lights have different colors?
The tubing is coated with phosphor, which will determine the color of the bulb.

What diameters of fluorescent tubes are available?These are the most widely used diameter fluorescent tube size is T-5, T-8 T-10, T-12. Bulb sizes (meaning diameters) vary from .25 up to 1.5 inch, the larger in diameter the larger the fluorescent.

What length is most used?
There is a wide variety of lengths from 6 to 96 inch, the most widely used is a 48 inch fixture.

What wattage is there to use?
Fluorescents come in a wide range of watts any where from 4 to 214 watts that I have found.

Why does my bulb flicker?
Fluorescent tubes are rated by hours, these hours vary by the manufacture, the most common rated hours are from 6000-22000 hrs. The bulb flickering can also be caused by a poorly seated tube (poor receptacle contacts), a ballast or starter going bad or a tube wearing out such as shown in the photograph.

How do I dispose of these lights when they are broke?
Although commercially generated fluorescent lights are required by law, to be handled separately from general trash. Residents are allowed to dispose of them with the rest of their household garbage.

Where can I purchase fluorescent tubes, and how much do they cost?
Fluorescents can be purchased at all home improvement centers, hardware stores, and most pet supply stores or you can go to internet sites. The cost may vary depending were you reside, but the typical cost is a few dollar's for a pack of two bulbs.

Who manufactures these lights?
These are the most reliable companies on the market today: Sylvania, Westinghouse, General Electric.

What are lumens?
Lumens are the unit of measure that state the amount of light output produced by a light source. The higher the lumens, the greater the light output. The standard fluorescent tube should produce at least (3000-3300) lumens.

How can I optimize the light output?
You can help reflect the light out of each tube, by using metal foil tape as a reflector, attached directly to the tube as shown in this faq. click here Using clear plastic safety sleeves over the fluorescent tubes allows you to recycle the metal foil reflective tape.

What is a Kelvin scale?
One way light is measured is on a Kelvin scale. A Kelvin scale expresses the exact color the bulb emits. Bulbs in the range of 2700 to 6500 on a Kelvin scale is ideal for growing marijuana. Plants respond not only to the quantity of light, but also the quality.

What color spectrums are available in fluorescent bulbs?
Fluorescent bulbs have the most range of spectrums than any other bulb. The spectrum comes in various spectrums, determined by the type of phosphor with which the bulb is coated. The following fluorescent types are as listed, along with what they may accomplish for you.

# Full spectrum fluorescent bulbs have all the colors of the Kelvin scale. This bulb is good for vegetation stage. Note: This spectrum fluorescent is used in hospitals nationwide in helping people with "depression".

# Wide spectrum fluorescent bulbs will restrict development of side branching, helps plants mature faster. This fluorescent is high in the red, orange and yellow color range. In fact, this fluorescent is the highest than all other fluorescent bulbs. As a matter of fact, this fluorescent is much like an HPS color range, which makes it the best all around choice for flowering stage.

# Daylight spectrum fluorescent bulbs are very high (if not the highest) in the blue range on the Kelvin scale. This fluorescent promotes an arctic blue look. I suggest this fluorescent during vegetation stage.

# Cool spectrum fluorescent bulbs will promote multiple side growth, nice green foliage. This fluorescent is high in the blue range, giving off a bright white appearance. I suggest this fluorescent for vegetation stage.

# Warm spectrum fluorescent, will promote extra thick stems and branches, and will give you about 5% denser buds than other spectrums. This fluorescent is high in the red range on the Kelvin scale.

# In the old school of fluorescent growing, an even mix of warm white and cool white tubes has been proven to be the best combination of light spectrums to use for flowering stage. If wide spectrum bulbs are unavailable in your area, then this is the combo to use.

Do fluorescent tubes need air circulation?
Fluorescent tubes do get warm, but not if they have adequate air circulation. A simple fan blowing over the fixtures as shown, will help a great deal to cool the tubes.
If its done properly, any stray foliage that comes in contact with the tubes will not be harmed.

Author: Captsneak
 
:thanks: Great post, Smokey. Too few people provide good information on fluorescents, which will continue to be the poor-grower's light choice for year to come. Fluoros are a great choice for a first time grow, and can be very effective IF USED PROPERLY, which is tough to do without people like you providing such great insight. Mad + rep.
 
Hey smoke, read your info on fluorescent usage,good food for thought. this is what I'm doing for that 13 week flower girl. I have 9 cfls. 27watts and 4 4ft. tubes the tubes are in one fixture, useing lots of foil all around my grow space. takeing your recommendation to let this girl grow for a few more weeks do you think I've got enough light.? thanks for being here... peace.
 
Sunny if you use mylar instead of foil around your grow space you will get better usage out of your lights. Mylar reflects more light then foil does. Aside from that is seems like you have PLENTY of light, though I do not know how many plants you have growing.
 
Hey sgroboyfresh, went to wally-world and got that mylar what a big difference, in light re-fraction. did my whole grow space with it .. thanks for the tip u guys... let the sun shine upon you all.. Peace.
 
Gr8 post. very informative. Im definitely going to more and different kinds of light.
 
I'm a newbie and I am starting my 2 autos with cfl's. I plan to use 8 23watt 6500k bulbs and change to 2700k when they start to flower. I also have a 150watt hps that I thought I would add when flowering starts. Any suggestions/comments?? Will this help or not?
 
I'm a newbie and I am starting my 2 autos with cfl's. I plan to use 8 23watt 6500k bulbs and change to 2700k when they start to flower. I also have a 150watt hps that I thought I would add when flowering starts. Any suggestions/comments?? Will this help or not?

Dpending on how you have the bulbs i.e. light bar 2 or a 3 way adapter you can use the cfl bulbs for side lighting and also the hps in flowering. I am using 5, 4 ft 2700kbulbs and a 2ft bulb of the same for side lighting and my hps is hanging above I rotate her everyday. No preflowers when i started and she is starting to bloom to a beauty.
 
I'm a newbie and I am starting my 2 autos with cfl's. I plan to use 8 23watt 6500k bulbs and change to 2700k when they start to flower. I also have a 150watt hps that I thought I would add when flowering starts. Any suggestions/comments?? Will this help or not?

seems like you should be ok. The HPS couldn't hurt. The more light the better! Research the journals.they are a great source. I am also growing autos using T8's and CFL's. I should have a journal up in a week.

Good luck!
 
Dpending on how you have the bulbs i.e. light bar 2 or a 3 way adapter you can use the cfl bulbs for side lighting and also the hps in flowering. I am using 5, 4 ft 2700kbulbs and a 2ft bulb of the same for side lighting and my hps is hanging above I rotate her everyday. No preflowers when i started and she is starting to bloom to a beauty.

Never mentioned the type of bulbs, they are T12 fluorescent
 
Never mentioned the type of bulbs, they are T12 fluorescent

T12's will do the job but I suggest adding some CFL's as well. T5's are better but as a newbie myself I understand how expensive they can be. I wanted so bad to start with T5's but the wife stopped me cold! I have since been put on a budget! So I am using 6 T8's and 12 100w equivalent CFL's. IMHO shop wisely the small stuff adds up! I have found it useful to check what I already have laying around the house or friends. Good luck! The other reply's you have received are full of good advice
 
T8 is the best all round bulb. whilst t5 is the most efficient watts/lumins it isnt much better than t8, but the mass manufacturing benefits of t8 dramatically reduce the tooling costs compared to t5. financially speaking, you can add so many t8's compared to t5s that the difference in cost can allow you enough t8's to out light t5s on the same budget.

I feel better already! T8's is all I can do at this point and I am fine with it. My first grow! I just want to get through it! Thanks for the advice.
 
Hello brothers and sisters of the green lady. i just start using a comb of just right xtra potting mix and root bags by aurora.hope to get a nice yield. with a 250 watts cfl lighting.any comments
 
Hello brothers and sisters of the green lady. i just start using a comb of just right xtra potting mix and root bags by aurora.hope to get a nice yield. with a 250 watts cfl lighting.any comments

Yes!! Do a journal. Folks will come by and offer their advice and help! Pics are helpful as well.
 
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