What's the difference between CFL and T5? When stealth is a growers biggest concern, fluorescent grow lights are the undisputed king. They make very little heat compared to HID(High Intensity Discharge) lights and LEDs, they tend to make a smaller impact on your electric bill, and they are much cheaper to get started with. They're also very beginner friendly since they don't require the purchase of secondary parts (such as an exhaust fan) in many cases and can be setup easily. I actually hooked up my first fluorescent lights with nylon rope I had lying around! But all is not well in this stealthy, new-grower-friendly world... There are two types of frequently used fluorescent lights struggling for superiority, each with their own benefits: they are the T5 fluorescent light, and the CFL (Compact Fluorescent Lamp). Today, you'll get the rundown on what's better about each one which will hopefully help you make a decision should the need arise.
CFL bulbs: CFL or Compact fluorescent lights are curved fluorescent tubes compacted in a small space and fitted with portable ballast that allows them to be fitted in regular household light bulb sockets. As Grow lights CFL bulbs have the advantages of being cheap , having easy and understandable technologies and also being compact. Because you can buy these light everywhere and everyone is using them in their home, you much rather have a well known technology than some outside ballasts and fixtures to worry about. And this is the major selling point on CFL bulbs but if we turn to what is better and more efficient for growing then CFL light do not look as good. These Compact Fluorescents lights are less efficient than almost any other fluorescent technology so they will use more electricity and won't be able to supply as much light power to your plants for the same price as T5 or T8 bulbs. CFL bulbs are oddly shaped so reflectors can't cover them fully and there is less light reflection from those reflectors. CFL bulbs are almost always available in small wattages so you will need to have a lot of those small bulbs to get some decent light penetration and growth! And when you can get them in bigger wattages they get more inefficient and that can become a big waste of electricity!
My final opinion about CFL bulbs is that they are good for small scale growers that want to try out growing something with artificial lights. Because there won't be a lot of savings in efficiency and also for small scale you don't need that much bulbs you can start your artificial light growing with CFL bulb. But if you are trying to grow larger crops or larger quantities than CFL lights become a huge waste of electricity and you need to do a lot of work to set them up! CFL light Efficiency: 13 W = 825 lumen => 63 lumen/watt 26 W = 1610 lumen => 61 lumen/watt 42 W = 2700 lumen => 64 lumen/watt 45 W = 2800 lumen => 62 lumen/watt 85 W = 4250 lumen => 50 lumen/watt 125 W = 7,000 lumen => 56 lumen/watt 200 W = 9500 lumen => 47 lumen/watt 300 W = 13,975 lumen => 46 lumen/watt
Pros of CFL Marijuana Grow Lights
Widely available. You can hang them close to plants. Good for small or short grow spaces. Low heat. Bulbs are relatively cheap. Bulbs fit in all kinds of light fixtures. Good for clones, seedlings and young plants (you would have to hang warmer, brighter marijuana grow lights further away to give the same light as close CFLs, thus wasting a lot of electricity). Cheap option for a first trial grow. Good for a single plant grow. Can be useful supplementing other more powerful lights. Not much extra ventilation needed.
Cons of CFL Marijuana Grow Lights
Not good for large grows (if you want to harvest more than a few ounces, for instance). Relatively low yield per watt, if used for whole grow cycle. Need to check on your plants and light placement daily. You'll have to learn how to train your plants to keep them growing low and flat (because fluorescent light doesn't penetrate far). Not as energy efficient as some other marijuana grow lights. Not as long lasting as LEDs.
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Other marijuana grow lights give better control of color spectrum emitted. Other lights are brighter, more powerful. Many other lights more easily and accurately mimic sunlight.
T5 bulbs T5 light are the latest generation of fluorescent tubes and they are meant to replace those T8 bulbs in efficiency and give better light output. These T5 tubes have again smaller width and it is 0.62 inches (15.9 mm) so they are more compact and have lower overall profile. T5 ballasts are smaller and that is why T5 grow light fixtures can also be thinner than T8 ones. T5 lights are more efficient than T8 bulbs but not by much and they have about 10% increase in efficiency but their price is considerably higher and that can be an issue. T5 bulbs also run with higher temperature because they need to be around 35 Degrees Celsius to be the most efficient whereas T8 light run at around 28 degrees Celsius. This is not a huge increase but can again be a problem for small grow operations or Hotter climates. Overall T5 lights are the best solution for growing because they are more compact and more efficient and because of that you can cramp more of them in the same space and give your plants more intense light that also costs less watt per watt than any other fluorescent light source. T5 light bulbs come in different sizes and Wattage output but each different manufacturer has slightly different bulb efficiency so be careful when you are choosing your T5 fixture. T5 light bulbs also come in standard configuration and High Output configuration but they have another and that is the Very High output configuration but the that last is not feasible for growing because it is about 20 to 30 % less efficient than HO bulbs. T5 light efficiency: Regular 6 W 9 inch = 290 lumen => 48 lumen/watt 8 W 12 inch = 400 lumen => 50 lumen/watt 13 W 21 inch = 850 lumen => 44.6 lumen/watt 14 W 22 inch = 1350 lumen => 96.4 lumen/watt 21 W 34 inch = 2100 lumen => 100 lumen/watt 28 W 45.8 inch = 2900 lumen => 103.5 lumen/watt 35 W 58 inch = 3650 lumen => 104.2 lumen/watt High Output 24 W 22 inch = 2000 lumen => 83.3 lumen/watt 39W 34 inch = 3500 lumen => 89.7 lumen/watt 54 W 45.8 inches = 5000 lumen => 92.5 lumen/watt 80 W 58 inches = 6600 lumen => 82.5 lumen/watt Very High output 95W 4 feet = 7200 lumen => 75 lumen/watt
Pros of T5 grow lights
As stated above, T5s run very cool and as such, they can be kept closer to your plants. In fact, they should be kept far closer to your plants than with non-fluorescent lights to maximize on their power. Since T5s can be kept so close to the plants, this means that growers can use smaller tents than they typically would with an HPS. T5s have a low impact on your energy bill compared to HID lighting. Possible to grow without exhausting heat which opens up growing spaces unavailable to HIDs.
Cons of T5 grow lights
Not as much power as HIDs, so yields will naturally be lower. Growers might have to check on them more often since they are kept closer to plants and have less buffer room.
Advantages Over CFLs:
CFLs can be placed into a reflector, but T5s are meant for growing and tend to be easier to use and adjust. Generally, moving a single T5 panel higher takes only seconds when it's hung with rope ratchets. In fact, T5s take less effort to set up and maintain in general. More efficient use of energy than CFLs (albeit marginally).