in Lighting Mon Nov 25, 2013 1:17 am
by ozzydiodude • The Weird One | 2.084 Posts | 10103 Points


Every grower has, or still uses these lights. Although they don’t even come close to the results from a HID light, they do however provide a cheap alternative for a newbie 'dabbling' in the fine art of growing. Instead of spending hundreds of dollars on an HID light, a newbie can purchase a compact fluorescent for a few bucks, and still have money for a coffee on the way home. These lights are also excellent for starting seedlings and clones, as their cool light will not dry out the soil as fast as an HID. They have a low intensity, and are gentle on newly germinated seedlings, and are great for clones as they wont dry them out or give them too much of an early blast. Compact fluoro's are also great for stealth grows, as they can be kept about 1 inch from the plants, and do not require extensive heat ventilation due to their warm operating temperature.

What are compact fluorescents and how can I use them for growing?

Compact fluorescents are close relatives of the 4ft tube fluorescents, commonly used in shops and schools for their white, soft light that does not cast any defined shadows. These lights are long tubes, usually 4ft long, filled with a gas that releases a photon of light when excited by electricity. The electricity is passed through the tube from the metal sections at either end, thus exciting the gas within and releasing photons of light. These lights must have a 'starter' which gets the light going initially, unlike incandescent which can just be turned on and off without one. Regular fluorescents usually emit 18w of light per tube, and cannot be plugged straight into a wall socket. Compact fluorescents, on the other hand, are made for use in regular light sockets, and can easily be installed by anyone with basic handyman skills. Compact fluorescents are usually around 8inches long (not including the ballast, which usually adds about 3 inches to the total length) and emit minimal amounts of heat from the globe itself. Most of the heat emitted from a compact fluorescent comes from the ballast. These lights are usually between 8w and 27w, although some variation may occur between brands and uses. The main reason people choose CF's over regular fluoro's is their compact ability! They are very 'movable' and can be positioned almost everywhere. They put out MUCH more light than their bigger cousins, while using only a fraction of the space. Some of the many varieties of compact fluorescents.


If you're running a large grow setup, and you're concerned about the spike in electricity, replace your regular light bulbs with compact fluoro’s around the house! They give off the same light, using only a fraction of the electricity. If you're running a HID light, and the electricity increase could kill you financially, or you're just worried about LEO, it might be a good idea to replace incandescent with compact fluoro’s. As an example, a 100w incandescent uses most of its energy giving off heat. If you replace all these 100w incandescent bulbs with ~20w energy saving compact fluoro's, you can dramatically reduce your energy bill, and help the environment at the same time. In fact, I recommend changing all your lights to CF's regardless of your growing situation, as they will save you $$ in the long-term, and save the environment. The advantage with these lights is that the conversion from incandescent isn't complicated! Simply un-screw the old bulb, and screw in a compact fluoro! Done! You're on your way to energy saving paradise!


Most lighting stores will sell them, but watch out, prices are very different depending on what type of shop you get them at! As lighting shops only sell lighting equipment, their prices can either be high or low, it really depends on the type of lighting shop it is. A designer lighting shop may end up being much more expensive, as they tend to be more directed towards the upper-class designer type customer, which extra $$ to spend. Hardware’s sell them, but their variety of lights is usually limited. Electricians, and assorted electrical shops will sell them, and this is most likely where you will get the best range and the best prices. My advice to you is, shop around! You wont regret it when you can save around 30% per light.


For anyone growing cannabis, it is pointless to buy a weak light. Given the option of 8w, 15w and 27w, you would be stupid not to buy the 27watt, as they are more or less the same price. Compare the lumen output of each of the bulbs, different 27w bulbs may have different lumen outputs (depending on the manufacturer) and as with everything, the more lumens the better. You will also be given 2 options, the screw method of fitting, or the bayonet method (push and turn). My preference is the bayonet fitting. Make sure that you choose the right one for your socket! Also, do not choose a regular compact fluoro. Pick the one with the energy saving feature (will be explained why later on in the document). Now, for vegetative growth you should choose the 'cool white' light. This is also acceptable for flowering, but a 'warm white' light will be better as it is stronger in the red end of the light spectrum which is more suitable for flowering.

Can I use foil on my florescents?

In a shop light type fixture, the bulbs are usually space a few inches apart. This type of reflector creates light "stripes" when used close to the plants. The hood on a shop light helps to widen the light by reflecting the light coming from the top of the bulb. When you use this style reflector the light never leaves the top the bulb, instead its reflected back through the bulbs and sent out the front. If you doubt this works check with any aquarium shop and ask them. The foil reflector: when you want the bulbs close to one another. OK, all you need is a bulb and some 2” wide foil tape. Now, cut the tape so it is a couple of inches shorter than the bulb. This is for two reasons. First, the bulbs get hottest on the ends (heat can make the glue release and the ends of the tape will pull up). Second, it keeps the conductive foil away from the power at the end. Before you start sticking the tape on, make SURE you have the bulb laying where the pins are horizontal to the floor. If your pins lock at an angle in the fixture, make appropriate compensations.

* Make sure you get the tape oriented with the correct florescent pin position when installed!*

stick to the very top the bulb. Keeping the tape straight, slowly run it down to the end. Tear off any excess at the end before sticking it past the last inch. Be sure to keep tension on the tape as you lay it - it helps to keeps the tape straight and centered (stops wrinkles). Now that the center of the tape is stuck, start at the middle of the bulb and slowly make the tape touch a little more from the center out so that the tape is starting to take shape of the bulb. Work from the middle to end of the bulb. Don’t try to get all the tape to stick in one try. The tape will not lift once set in place. Note: trying to stretch a full length of foil tape and trying to lay it all-at-once onto the bulb is extremely difficult; if the tape touches anything it'll stick hard, and it tends to curl when you peel off the backing. The results I took a comparison picture. The taped bulb is brighter and the light is focused downward. You still have some side lighting but as you can tell it is much less. The last picture is of a bulb that is over 30 days old and it shows no sign of phosphorous burning, stress or damage. Using this technique you can literally create a wall of light. Floro's are not known for their power, so be sure to get all the light you can get out of them.
Editors Note: If your foil tape doesn't have clear adhesive, mylar can be used in it's place.


Now, this is extremely easy. As these bulbs fit normal light fixtures, you can just dismantle and old lamp to get the cord, plug and bulb fixture. This is ready made, as all you have to do is plug the cord into a wall outlet and screw in a bulb (with the power turned off, of course). This requires no electrical knowledge at all, and is the easiest way to get a cord suitable for a compact fluoro. The cord is simply removed from the lamp, and you are ready. If you feel you are not up to this task, or you do not have an old lamp ready to be destroyed, you can easily make one of these cords with basic electrical knowledge. Hardware’s and electricians will sell you the cable (you'll need at least 1 meter) and the fittings for the wall socket and the light. Just tell them you're making a lamp for pottery and need a few cables to make up yourself. The parts are cheap, and you can save $$$ this way. If you have any queries, the electrical store will know exactly what type of cables you need etc, and will be more than happy to give you instructions on how to put it all together. Please note that this is a guide for regular compact fluoro's. There are some outdoor varieties (which are rare) that need to be fitted specially. This FAQ is written for the regular compact fluoro’s, the ones that are most accessible to the general population. Other varieties of compact fluoro's are hard to find, but may or may not be better for growing. As I have little experience with these rare lights, I cannot comment on them. The reason I haven't seen them before, is because they are almost non-existent where I live.


build this reflector you will need a regular soda can, any brand will do, which you will need to rinse thoroughly until no residue is left inside. You will also need a good pair or scissor and a robust kitchen knife to cut the metal accordingly. An alternate method to remove the lid, would be to use a can opener. The lip of the lid can be used, and it will cut it cleanly. These tools should be chosen carefully as they will determine over failure or success of this construction. A lack of caution and a sharp metal edge can be fatal to your fingertips so think twice if your tools are capable of doing the job.
How and where to cut: Firstly, draw a plan of your cutting path on the outside of the can using a permanent marker or a wax crayon. This will aid you to get a better overview of you plan and to avoid silly mistakes on the way. Cutting the top part of the can out needs to be done first, adjusting the opening according to the size of your bulb. You do not have to cut it exactly to shape as glue (super or high-temp hot glue) can be used to stick the reflector to the bulb ballast later on. A can opener is the preffered tool for this job. The reflector is purposely not covering the ballast to ensure good aeration and to avoid damage to the ballast components, resulting in a short circuit. Next, you will need to cut the main part of your soda can in half using your scissors. A hole may need to be drilled first using your kitchen knife to get a good starting point for the scissors. The inside of the can is coated with a thin plastic layer that should not cause any trouble cutting through the sheet metal. The bottom side of the can does not have to remain in place but leaving it will add stability to the reflector and enhance the reflectivity. An extra hole can be cut into the bottom as well to improve ventilation along the bulb or to connect a 50mm pc-fan to the end. Lastly, two more cuts have to be made into the sides of the semi-circle reflector to ensure that the sides do not reflect the light back to its origin but rather focus it to where it is needed. The reflector can now be bent according to your light requirements thus making it possible to focus it directly on your plants. If your reflector does not quite fit the bulb yet you can now use glue to stick it to the ballast.


When purchasing a compact fluorescent, you will notice that nearly all of them have a larger number on the box, than what it actually is. This number is the lights comparison to the brightness of a standard incandescent globe. Do not be fooled, this does not mean that the light is 100w! It is most likely around 18w. Now, here is where the myth behind these lights is uncovered. Most people will say that you should totally discard the brightness rating. This is wrong! The brighter a light is, the more penetration it has. With a usual, run-of-the-mill compact fluorescent (say, 15w) it emits only 15w of light with poor penetration. An energy saving compact fluorescent with 15w of light, which is rated to 100w of light, will only emit 15w of light. The difference between the two is, the energy saving light has a much stronger light penetration of the normal one, while still only emitting 15w of light. This is beneficial to growers because with a larger plant, a normal 15w compact fluoro will sufficiently light one part of the plant, and by the time the light has reached the other side of the plant, so much of the light has been lost that it is barely worth having. With the energy saving compact fluorescents, the light will travel to the other side of the plant, and still have enough intensity for reasonable results.

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