what lighting is best to use for plant growth.

hi, im busy planning an Led lighting system.
but im not sure what LED is best to use.
do i go for the led with a multi color spectrum or do i go for the leds that are the brightest ie. 5500- 6500K .

or what is the best light spectrum to use?
quite ignorant on this topic so please ... educate me
thanks

 

not really able to ans but would like to see what people say, would be interested tho , saw some high power spots , running on 12v, which i would like to be able to use, ( more correctly floodlights , i guess) 800/850 llumens, at 10 watts, 6000/7000k. so would be quite keen to know, as eventual plan is to off grid the tanks,

 

Would also like to know. Im just using the normal bulbs thats in the lfs. Have 3 25w boyo lights in 100l setup. But dont think its good enough for my plants i dont know also. Would love to know what the experts think

 

6500K - 10'000K is best for plants. A lot of people will say you need a blue light, or red light as well... Maybe if you are trying to go very high tech, but not otherwise. With the LED's you will rather have to spend your money on some LED's with great water penetration and with good coverage (it won't really help if you have 4 bright spots in your tank, and the rest is dark).

If you do a tank according to the Walstad method, then you will need to incorporate some multicoloured LED's as well, or if you want to include other colours for effect. I have seen someone say that white LED's is only white and does not include other colours as florescents do... well, go look up white light if someone tell you that... White light is the combination of all colours... 6000K does however mean more blue is present that red.

Also, remember that light is not the only thing your plants need. They also need a good substrate and some ferts if possible. Even CO2 if you are going higher tech. So Ryno, 75W in your 100L would be awesome for some algae growth if you do not include good substrate, plant food and CO2. You could pick up a bottle of Seachem Excel from Jacque. The instructions says it all. You could also buy online from one of the sponsors. onlinepetshop.co.za (Pet Stop) has some great prices on Seachem products and the courier to Potch does not take that long.

 

i use exel and trace. and trace. i actually used pottingsoil with with peatmoss? and vermiculite and covered it with gravel. the one tank of mine grows with just 2 lightbulbs but my other tank with 3 is struggeling. only thing i get to grow in it is hysteria?

 

Then the next question would be what is in that tank that does not want to grow. Plants? Fish? Filter type? Filter media? and the type and age of your lights

 

i use an aquaclear power filter 50. other plants is indian fern some moss dont know wich one. and a BL plant im not allowed to name haha. fish ramirezi's, ancistrus pleco, rainbowfish (removing shortly, x-Ray tetras and some panda corrys. i use the seachem products as they describe it on the label.

 

going a bit of topic, but info is always good. So what does not grow? Your moss and Fern? If you BL plant does not grow, then you have some issues. What media do you use in your filter? AC will remove some of the traces you pay so much for...

 

fern like disolves or melt at the bottom. moss grows very slowly. o and i have anubias? think the spelling is right. they are slow growers and they do fine. i use the seramic rings and that amonia remover stuf and the spunge. no AC the moss has allot of dull eareas. anubias has black spots on some of the leaves. my water temp is constently at 27C

 

and my ph is 6.5

 

Nicely done on having a pH of 6.5 in Potch . You could try turning one light off. Some ferns and anubias grow slower and melt with very high lights and I know some vali's and a fern here and there melt with Seachem Excel (something I heard a looooong time ago, might be misonformation)

 

my indian fern also have some black spots. everytime i do a waterchange i use oasis water. use peat and also 2 airstones. i use half oasis water half tapwater. does wonders everytime i do the waterchange my rainbows gows in spawning mode the next morning. egg breakfast for the corys and ramirezis. dont have extra tank ect to breed them so ja. all my fish are healthy just not the plants.

 

ok so i can go for the leds that are 5500 - 6500 K and that should be fine for plants ? you guys have kinda gone way off topic here from what im really trying to find out!!
from what i could understand from your first reply...@DigiGram is that the hight the K rating for the (white) lights the better it is for plant growth!!! is this true?

 

Sorry i hijacked the tread.

 

Well, thats the first part of the theory. If you take a look at blueish light, it has a K rating of a 100'000+ (might be even more). Blue light has infinite K, while red is down in the 1000-2000K range. So higher is better, until a point where to little red is introduced and to much blue. Diana Walstad argues that aquatic plants prefer green and yellow light since blue does not penetrate lakes so good in nature, but from experimenting a lot of people have found that tanks with more blue than red (higher K) works better. The general consensus is 6500 - 8000K, but a lot of people like to include some pinkish and extra blue lights.

If it were me I would use the 6500K LED's, and with time introduce a couple of blue LED's for effect.

 

The K-rating of the light is responsible for the colour of the light. If i am not mistaken the higher the k rating the bluer/whiter the light? And the less k rating is more red? Kelvin rating is the colour temperature of the light? Anyway 6500k i what you want to go for when growing plants, at least thats what i'm being told lol!

 

Yster is correct on calling it the colour temperature of light, but this confuses most people. Think of heating a black piece of metal (the theory uses a black radiating body). As it heats up it gets red, then white (wit-warm), and next it will start to glow blue. So the higher the K, the closer you get to blue. 6500K is a nice mixture of red and blue looking white to our eyes.

 

Kelvin is a bad way to measure lights for an aquarium as you can "make up" different kelvin temperatures by adding different light frequencies together in different amounts.
6500k white lights do have sufficient available photosensitive light to support light in principle.
Your best light? long term LEDs DESIGNED FOR THE PURPOSE such as TMC grobeams and Arcadia's products all do very well and *sound* expensive.
In my tank, if I were to substitute 2x 20W T5s for LEDs, here's how it compares in terms of costs:
3 years:
R400 per set of tubes / 6 months: R2400
Fitting: R600
Total hardware: R3000

2x TMC Grobean 500s @ 12W: R3000
(Guaranted 5 yrs)
Even without electricity savings a 3 year payback period is very good no?
cb

 

That's the whole point! Those LED's do the same, they combine the light frequencies that the plants need. Even if you like to argue that you can 'make-up' a certain proven Kelvin rating while skipping some important frequencies of light (If you try hard enough I'm sure you will be able to accomplish that), enough research has shown that normal fluorescent's do a good enough job for plants. Go check out some of the plant dedicated South African forums.

In your comparison, 2x 20W fittings, can't cost you R600?? I'm sure even the T5HO must be cheaper than that... Also, I assume you were using some 'specialized' T5's to run at R200 each for a 20W? You should've tried better substrate and rather included an Osram Daylight fluorescent that would've been way cheaper.

While you do have the LED's running, try adding some good substrate as it will enhance your plant growth more than your expensive lights will. I do believe that LED's are the future, but for aquaria currently I think it is still the future and not present (but if you do have thousands to spend on overpriced LED's, do it now)

 

600 was what the LFS quoted me on but here goes:
Onlinepetshop SA: R480 - cheapest 60cm fitting they have there
Same store: R231 for a 60cm T5HO 24W a little bright but in the general replacement range.
Total R3009 (as the fitting comes with 2 tubes.

As for the science... If you read cree's binning methods and know that TMC has exclusive rights to market a specific "BIN" of LED produced for the aquarium, then you can infer that a bit more homework's gone into the product. I put it to you that there's more than a temperature match going on with specific bins being matched that produce more PAR