# What makes an led light able to grow plants?



## aquariumrookie (Jun 26, 2014)

Hey guys!
I have 4 aquariums and all but 1 use CFL lights or flourescent light tubes to grow plants or just to illuminate the aquarium. I got a new aquarium today (some kind of topfin 10 gallon aquarium kit with filter, led light aquarium, hood, and heater).
I was planning on growing plants with it when I realized the led lights it came with were not very bright. So, I was considerig purchasing a DIY led system (led adhesive light strips). However, I hear these leds will not support plants.
So, here is my question: what aspects of certain led lights supports plant life and how can i make the cheap adhesive led strips support palnt life?
THANKS!


----------



## Seattle_Aquarist (Mar 7, 2008)

Hi aquariumrookie,

The same aspects that support life with CFL or fluorescent tubes applies to LED lights....intensity and spectrum.

You are correct that the 10 gallon kit LED light may not support plant growth; I have seen those kits and the LED lights are more for viewing fish than growing plants. I question whether the adhesive LED strips can provide the amount of light necessary (btw they may claim to be sealed but not really).


----------



## aquariumrookie (Jun 26, 2014)

Is their any way I can kind of guess the kelvin or spectrum ratings of leds just by looking at them? For instance, a 6500k bulb looks pretty white compared to a 2700k bulb. Also, is it true that as long as the led lights' kelvin rating is around 6500k it can grow plants?
THANKS!


----------



## Zapins (Jul 28, 2004)

LEDs are interesting. Compared with other types of lighting LEDs can convert a large % of the electricity running through them into light which means that wattage is a pretty good indication of intensity. As long as the color temperature is in the right general range (5,000-10,000K) it should be able to grow plants if there is enough wattage behind it. 

For a 10g tank I'd say about 10-20 watts of LED light should do the trick depending on how the lights are configured.

It is best not to try eyeball the kelvin rating, it won't be very accurate.


----------



## TropTrea (Jan 10, 2014)

I have been having great luck running only 3 Watts of quality LED's on my ten gall plants. Mind you these are breeding tanks with floating plants and not high light demanding plants. 

There is alsot of caution with DIY and even manufactired LED' lights. First off differences in manufacturers LED's produce anything from 70 to 120 Lumins per Watt. Some even claim they will have 200 lumins per watt out before the end of the year for public availability. 

The second big fator is the spectrum and getting the right balance. Cool Whites LED's produce a lot of blue light and very little red light. You can get an excess of blue and shortage or red with these LED's on some plants. Therefore many people suplement red LED's with these. Neutral Whites (4,000K) produce a nice balance but for some plants are a little shy on the blue light. I have my best luck so for with a 50.50 split between the cool and neutral whites. Otheres use different bulb combination even using warm whites sparingly to boast the red spectrum. And others even suplement with red LED's.

A good color spectrum balance can be obtained in many ways but what might wrk for some plants may not work as good for other plants because of there desired balance between red and blue light. 

Think of it as Blue Green plants usually need more red light, yet bronze, yellow and red plants like more red light.


----------



## micheljq (Mar 25, 2013)

About led strips some aquario were able to do something right for a small tank with easy plants. They had to put 4-5-6 led strips to achieve enough intense light.

Michel.


----------



## TropTrea (Jan 10, 2014)

aquariumrookie said:


> Is their any way I can kind of guess the kelvin or spectrum ratings of leds just by looking at them? For instance, a 6500k bulb looks pretty white compared to a 2700k bulb. Also, is it true that as long as the led lights' kelvin rating is around 6500k it can grow plants?
> THANKS!


By just looking at then no. However if you have a film camera there is a way of quaging the approximate K by how the photo color gets distorted from the real life colors. Film is more sensitive to K temperature differences than the naked eye,


----------



## redthumb (Apr 17, 2014)

Has anyone tried the up-aqua led lights


----------

