How important is it to have Blue and Green in the light?

Mark Keetch

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So I'm proper new to this side of the hobby. I've kept fish for years but have never come down the aquascaping road. So I just have a pretty basic LED light unit. I can see it has white LEDs and a few blue LEDs in it too. I've been watching some videos on aquascaping and noticed the LEDs have White, Blue, Green and Red in them. Now I'm guessing the red is mainly for red/pink plants.

How important is it to have Blue and Green in the light to be successful in a planted tank. Baring in mind it's my first one so I will only be going low/medium tech with C02 and Liquid Ferts.
 

Tim Harrison

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How important is it to have Blue and Green in the light to be successful in a planted tank.
Not very...Most light units used in the hobby probably emit enough light of appropriate wavelength in the photosynthetically active spectrum to ensure healthy plant growth. What's perhaps more important is that we find the results aesthetically appealing.

By a happy coincidence of evolution the photosynthetically active spectrum and the visible spectrum are one and the same give or take a few nm, so what works out well for aesthetics usually works well for plants too.

LEDs have revolutionised the market, which has meant that lights can be customised to bring out the colours in both critters and plants and therefore improve the viewing experience. RGB units seem to be very popular choices for this reason: not necessarily because they have magical properties that promote miracle plant growth, which is what many manufacturers would have you believe.
 

Mark Keetch

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Not very...Most light units used in the hobby probably emit enough light of appropriate wavelength in the photosynthetically active spectrum to ensure healthy plant growth. What's perhaps more important is that we find the results aesthetically appealing.

By a happy coincidence of evolution the photosynthetically active spectrum and the visual spectrum are one and the same give or take a few nm, so what works out well for aesthetics usually works well for plants too.

LEDs have revolutionised the market, which has meant that lights can be customised to bring out the colours in both critters and plants and therefore improve the viewing experience. RGB units seem to be very popular choices for this reason: not necessarily because they have magical properties that promote miracle plant growth, which is what many manufacturers would have you believe.

Thanks Tim. That's good to know. I dont really fancy forking out hundreds for a new light unit to be able to do it right. I stick with the light unit I got for now then :thumbup::thumbup:
 

PARAGUAY

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And making more confusion some manafactufacters advise their lights specially for plants are the only way to grow them , ok till you stumble on a nice Dutch scape lit by simple shop lights
 

jaypeecee

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How important is it to have Blue and Green in the light to be successful in a planted tank. Baring in mind it's my first one so I will only be going low/medium tech with C02 and Liquid Ferts.

Hi @Mark Keetch

It is important to have both blue and green in the light to be successful in a planted tank. Both are required for optimum growth. And if there was no green light illuminating your plants, they wouldn't look green! Red light is also required, not only to make your red plants zing but plants need it for growth. But, white LEDs contain a lot of blue, less green and even less red light. So, an LED fixture that includes white and red LEDs should perform better than one with just white LEDs.

JPC
 

Mark Keetch

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Hi @Mark Keetch

It is important to have both blue and green in the light to be successful in a planted tank. Both are required for optimum growth. And if there was no green light illuminating your plants, they wouldn't look green! Red light is also required, not only to make your red plants zing but plants need it for growth. But, white LEDs contain a lot of blue, less green and even less red light. So, an LED fixture that includes white and red LEDs should perform better than one with just white LEDs.

JPC
Thanks bud. Something to bare in mind further down the road. Mine just have white and blue so might need to invest in a new unit at some point.
 

Tim Harrison

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Hi @Mark Keetch

It is important to have both blue and green in the light to be successful in a planted tank. Both are required for optimum growth. And if there was no green light illuminating your plants, they wouldn't look green! Red light is also required, not only to make your red plants zing but plants need it for growth. But, white LEDs contain a lot of blue, less green and even less red light. So, an LED fixture that includes white and red LEDs should perform better than one with just white LEDs.

JPC

In relation to the OP, there is usually more than enough electromagnetic radiation, or light, of different wavelengths in white light to ensure healthy plant growth, especially high output LEDs used in aquarium lights. Relatively speaking, RGB lights are mainly a benefit to aesthetics.
 
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Hi @Mark Keetch

It is important to have both blue and green in the light to be successful in a planted tank. Both are required for optimum growth. And if there was no green light illuminating your plants, they wouldn't look green! Red light is also required, not only to make your red plants zing but plants need it for growth. But, white LEDs contain a lot of blue, less green and even less red light. So, an LED fixture that includes white and red LEDs should perform better than one with just white LEDs.

JPC

Good news, this is exactly how I run my lights!
 
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