[ivas]

Hey guys,

Was at the store and noticed that they now make 40W equivalent screw-in LED light bulbs. Before I give one a try, I was wondering if anyone else has tried them? Do they emit the correct wavelengths for plants? Does the light "penetrate" far enough to reach the bottom of typical terrariums?

Shop Utilitech 40-Watt Equivalent Indoor Soft White LED Light Bulb at Lowes.com

Tom

 

[shazzbott]

It says the color temp is onlt 3000 for plants it should be 6500, therfore is wont work.

 

[jsh21]

Tom,
A bulb with a color temp of 3000k will also make your frogs and plants appear to be somewhat different colors than what they would be in natural lighting. The 6500k range bulbs render colors much better. I had a tank with 1 4500k and 1 6500k bulb over it. After a couple of months the plants had all leaned toward the side of the tank with the 6500k bulb.

 

[charlesbrooks]

I believe these would work better.
E27 44 SMD 5050 White 11W LED Light Bulb Lamp 110V-220V | eBay

 

[motydesign]

did a lot of research into this, besure you understand the curves if you are hoping for any plant growth from these
http://www.dendroboard.com/forum/parts-construction/68416-marineland-led-lighting.html

 

[Scott Richardson]

Plant grow lights are actually around the 2700k range with a reddish orange glow. The plants lean to the 6500k because the light is actually a brighter light.
A good light source would be a combination of both types of bulbs. The 2700k causes plants to bloom and flower, the 6500k makes colors more vivid and bright.

 

[ryan10517]

you have to think about light intensity. LED's are not very advanced at this point of time, and are really expensive without many advantages against regular fluorescents. It would take almost four of those bulbs to be equivalent to a 26 watt spiral cfl that is half the price. Not to mention that 3000k is very yellow light and not the best for plants

 

[Scott Richardson]

According to all the plant growing light web sites, 3000k is ideal for plants. Just not good for OUR eyes looking at the plants under the yellow light.

If you look at a plant grow bulb, they are pink or yellow

 

[Scott Richardson]

I got a 48" strip with 60 high intensity bright white(6500k) leds for $12 and the DC converter was $24.

Not too expensive

 

[Shade71]

Here's some pics from my foray into LED's (I was trying to reduce the temperature in my terrib tank).
After a month I switched back to my old fluorescents (plus a better fan system) - the LEDs were bright enough, but IMO it was a very 'cold' light and just couldn't compete. The greens looked weird.
The plants looked healthy enough (but it was only a month).
I also had another tank with the old lighting nearby so I always had something to compare it to. Maybe on its own I would have gotten used to it.

Specs from the manufacturer...
Voltage: 18-20
Current: 2A
Wattage:36W
Color temp.:6500
Each LED circuit consist of 6 serial LED voltage 3.2-3.5 +1/8watt 100Ohm resistor protection.
150x6LED in parallel circuit.

 

[Shade71]

I should also say the light was obviously made for a more general purpose than the one I was using it for - as big bright light it works great.
The panel is about 12" by 30".

 

[LZeppelin513]

Look at the action spectrum (graph B). That tells you how much photosynthesis occurs at a given wavelength.

You can see that the peaks are around 440 and 660 nm (basically red and blue). If a plant receives light at only those two wavelengths from a bulb, you will still observe very positive results.

Regarding color temperature, you are essentially getting an average of the wavelengths from the light source; ie increase blue, increase color temperature.

With an incandescent bulb, color temp is a fine way to estimate photosynthetic activity because the bulb puts out light very evenly across its radiation range.

However, LEDs and florescent bulbs emit with large peaks. This means, for example, a bulb could potentially put out all its light at around 550 nm. This results in a color temperature around 5000k (which seems like a "good" temp to grow). However, in this case nearly zero photosynthesis occurs (verify by looking back to the action spectrum). So, with LEDs and florescent bulbs it is impossible to predict photosynthetic activity unless you are able to find the output spectrum of the bulb.

For instance, if the led bulb under question emits its light with very large peak around 660 and a somewhat smaller peak around 440 it would be nearly ideal for plant growth, all while measuring at 3000k color temp.

Ultimately, unless the manufacture is able to supply output spectrum data, you will just have to experiment with those particular bulbs and hope for success.

 

[dartfrog2011]

looks expensive

Here's some pics from my foray into LED's (I was trying to reduce the temperature in my terrib tank).
After a month I switched back to my old fluorescents (plus a better fan system) - the LEDs were bright enough, but IMO it was a very 'cold' light and just couldn't compete. The greens looked weird.
The plants looked healthy enough (but it was only a month).
I also had another tank with the old lighting nearby so I always had something to compare it to. Maybe on its own I would have gotten used to it.

Specs from the manufacturer...
Voltage: 18-20
Current: 2A
Wattage:36W
Color temp.:6500
Each LED circuit consist of 6 serial LED voltage 3.2-3.5 +1/8watt 100Ohm resistor protection.
150x6LED in parallel circuit.

 

[ryan10517]

Look at the action spectrum (graph B). That tells you how much photosynthesis occurs at a given wavelength.

You can see that the peaks are around 440 and 660 nm (basically red and blue). If a plant receives light at only those two wavelengths from a bulb, you will still observe very positive results.

Regarding color temperature, you are essentially getting an average of the wavelengths from the light source; ie increase blue, increase color temperature.

With an incandescent bulb, color temp is a fine way to estimate photosynthetic activity because the bulb puts out light very evenly across its radiation range.

However, LEDs and florescent bulbs emit with large peaks. This means, for example, a bulb could potentially put out all its light at around 550 nm. This results in a color temperature around 5000k (which seems like a "good" temp to grow). However, in this case nearly zero photosynthesis occurs (verify by looking back to the action spectrum). So, with LEDs and florescent bulbs it is impossible to predict photosynthetic activity unless you are able to find the output spectrum of the bulb.

For instance, if the led bulb under question emits its light with very large peak around 660 and a somewhat smaller peak around 440 it would be nearly ideal for plant growth, all while measuring at 3000k color temp.

Ultimately, unless the manufacture is able to supply output spectrum data, you will just have to experiment with those particular bulbs and hope for success.

Well put! i was about to post the same thing with a similar picture, but you beat me to the punch lol. There are few LEDs out there that are ideal for plant growth, but nothing beats a good linear fluorescent bulb though!

 

[bkelley02]

Does anyone know how the LED hoods from AAAfrogs are? Do they work well for plant growth and viewing? They sure look bright, but bright doesn't equal good.

 

[arielelf]

I just ordered one of their hoods today for my very tall, 36" high, exo-terra. It is a custom build. I am very excited to see how it comes out. They claim to use LED's of different spectrums for optimal plant growth, which sounds great.
I will report on how it turns out in a few weeks after my build is finished.

 

[bkelley02]

I ordered one as well a week or so ago. Parts should be in this week so I'm hoping to get it at some point next week. Interested to see how they look on a tank and not on youtube.