Amozoc
Premium member
White
Virtually every LED setup uses white LEDs as part of the base for the color of the light. The main reason for this is that is covers virtually all of the visible spectrum, and fills in some of the valleys that direct color LEDs miss. Different color temperatures (CCT) offer different effects, with some features being better or worse depending on the CCT.
Cool White (6000K and above)
While being used in the industry for the longest time, they aren't necessarily the best option due to the generally poor color rendering offered. They traditionally lack a lot of red content in their spectral output, and as a result, make reds, oranges, and pinks look dull. The higher the CCT, the worse the effect, and the more cold and stark the light will end up looking.
They do have an advantage in efficiency and output over warmer whites, and can be useful in full spectrum setups that have a lot of diverse control over the spectral output. As a general rule though, they aren't the preferred option, even though most mass produced fixtures use them.
Neutral White (4000K-5500K)
These are generally accepted as the go to base white color. The increase in red output, as well as the reduction in blue really helps with overall color rending, and the CRI (color rendering index) is usually a lot higher. Even cheaper neutral whites will have a CRI of 70 or greater, versus around 60 CRI for a typical 6500K cool white.
The relative output compared to cool white LEDs in the same series is lower, but not by as much as it used to be. It's not really that great of an issue though, as the blue LEDs will generally make up for any loss in performance, and the advantage of the higher CRI completely outweighs any loss in output and efficiency.
Warm White (2700K-3500K)
While not generally used by themselves as the base white, they are great when used in tandem with higher CCT whites. Warm whites will have very little blue output, lots of red, and very high CRI, with some of them getting up to 98 CRI. These are a great way to add warmth to the light, and improve color rendering in reds, oranges, and pinks without resorting to direct color red LEDs, as they tend to blend far better with the rest of the array.
Direct Color LEDs
Direct color LEDs make up the bulk of the color options available right now for LED setups. The material and doping process for the LED die creates the emission wavelength of the LED without any modifiers, like phosphors that are used in white LEDs. Because there is no down conversion of the energy emitted by the LED die, the efficiency on these LEDs is generally very high. They are very peaky though, meaning they emit light in a very narrow range, and the various color don't overlap a lot. This is the reason that white LEDs are used in conjunction with direct color LEDs, so the valleys between the different wavelengths is filled up, even if it's only a little, depending on the wavelength. We will start low and work up in wavelength.
UV-A (315-400nm)
Ultraviolet light is in the 100nm-400nm range, with UV-A being the 315nm-400nm end of the spectrum. UV-B and UV-C are not even considered here, as they are damaging to tissues. UV-A doesn't get used very often either, but will be found in every fluorescent and gas arc discharge (metal halide, HID) lamp due to the mercury used. Some, including myself have speculated that UV-A can actually be beneficial for coral health and color, but hasn't been proven effectively (at least from what I have seen so far). The big detractor from UV-A LEDs, especially in the 365nm range (mercury spike) has been cost. They are outrageously expensive, and with little known benefit, are generally avoided. UV-A LEDs hovering around the 400nm range aren't really of any use, and the photosynthetic action curve falls off sharply around this point.
As for coloration in the tank, there is very little discernible difference when these are used, as the human eye isn't very sensitive to these wavelengths. When used alone though, they can bring out fluorescent colors that aren't normally seen when using light in the visible spectrum. Due to the potential health risks though, especially regarding the eyes, they aren't recommended for use.
Violet (400-440nm)
Violet LEDs are for growth, not color. Like UV LEDs, the eyes aren't all that sensitive to this light, so the effects when used in conjunction with the primary white and blue LEDs are minimal at best. What they are good at is producing PAR, and lots of it. These are a great way to add growth potential without messing with the color temperature of the light. Caution should be taken with LEDs in this wavelength range, as you can't tell how intense they are, but the corals certainly will. Without proper care, corals can be easily bleached.
Royal Blue (440nm-465nm)
Royal blue LEDs are the muscle used to bring up the color temperature to more reef friendly levels, as well as producing a lot of PAR. They are also one of the best producers of fluorescent colors in corals. Royal blue, compared to blue (or cool blue as some call it) is a deeper color that doesn't illicit the "Windex" look. LEDs in the 440nm range tend to look a little more purple compared to common 450nm-455nm LEDs. When combined with neutral or warm white, the overall light can look a little purple, with the effect exaggerated the lower the CCT of the whites get, and the lower the wavelength of the royal blue LED.
Blue (465nm-485nm)
Blue was initially considered a supplemental color, meaning that it made an effect to the light and coral color, but wasn't really necessary. That's changed though, and it really is a beneficial color that should be used in all arrays, although sparingly.
Blue LEDs do a great job of fluorescing reds and oranges that royal blues just can't touch. They also help to take some of the purple tint out of the light that you can get from a neutral/warm white and royal blue mixture, as well as making the light a little crisper. Too much though, and the tank can look like Windex, so they either need to be used with restraint, or put on a separate channel to be controlled independently.
Cyan/Turquoise (485nm-500nm)
Cyan, or turquoise, is on the falling edge of the large blue photosynthetic peak, so it's not great for growth purposes, but it does have some useful effects on the color of the light and corals. Much like blue, cyan brings out fluorescing colors that other wavelengths don't. they are also good at making the light more crisp, and reducing the purple tint that you can get. It's another color that has to be used sparingly, but it's not as damaging to the color of the light as blue is.
Green (520nm-550nm)
Green does very little other than making the light brighter to the eye, and helping to reduce the purple tint. It really doesn't make anything fluoresce in a way that other colors would, and provides virtually no growth benefit.
Amber (585nm-595nm)
Amber is not used very often, as it doesn't produce much effect. It can help increase color rendering with cool white LEDs, but warmer whites typically have higher amber content anyway, so they don't provide much benefit.
Red-Orange (610nm-620nm)
Red-orange falls into the same boat as amber.
Red (620nm-645)
Red can help with color rendering more than amber and red-orange, as this is the area that most cooler white LEDs are lacking. It's also more in the red photosynthetic peak, so it has some growth benefits. Because our lighting setups are generally more blue heavy though, red can be very distracting when not used properly. Generally, warm white LEDs can be used to better effect to get the same color rendering advantage.
Deep Red (650nm-670nm)
Deep red doesn't have as great of an effect on color rendering as red does, but it can help with very specific color requirements. It was believed to have better growth properties than red, but that idea is starting to fall out of favor. Deep red is being used less and less.
Phosphor Converted Color LEDs
This is a fairly new development in LED technology. These LEDs use a royal blue LED as a base, much like white LEDs, but use selective phosphors to produce a different color. Unlike direct color LEDs though, the output is over a much larger range of wavelengths, and can have some greatly different effects compared to their direct color counterparts.
Lime (566nm-569nm)
566nm-569nm is just the peak wavelength, as these LEDs produce light in the 500nm-620nm range (measured at the 50% output point). The peak wavelength is higher than a typical green, and it actually coincides with the peak human eye sensitivity. This LED was designed with that in mind, as it was intended to help brighten the light, without adversely affecting CCT (something that just green alone can't do). This color can make the light a lot brighter as well as completely eliminate the purple tint that you can get with neutral white and royal blue combinations.
PC Amber (588nm-592nm)
Much like the lime, that's just the peak wavelength. Emitted light ranges from 540nm to 625nm (measured at the 50% output point), and is more intended to help with color rendering without negatively affecting CCT. Much like the lime, it can easily replace amber and red-orange to better effect
Sent from my iPhone using Thor
Virtually every LED setup uses white LEDs as part of the base for the color of the light. The main reason for this is that is covers virtually all of the visible spectrum, and fills in some of the valleys that direct color LEDs miss. Different color temperatures (CCT) offer different effects, with some features being better or worse depending on the CCT.
Cool White (6000K and above)
While being used in the industry for the longest time, they aren't necessarily the best option due to the generally poor color rendering offered. They traditionally lack a lot of red content in their spectral output, and as a result, make reds, oranges, and pinks look dull. The higher the CCT, the worse the effect, and the more cold and stark the light will end up looking.
They do have an advantage in efficiency and output over warmer whites, and can be useful in full spectrum setups that have a lot of diverse control over the spectral output. As a general rule though, they aren't the preferred option, even though most mass produced fixtures use them.
Neutral White (4000K-5500K)
These are generally accepted as the go to base white color. The increase in red output, as well as the reduction in blue really helps with overall color rending, and the CRI (color rendering index) is usually a lot higher. Even cheaper neutral whites will have a CRI of 70 or greater, versus around 60 CRI for a typical 6500K cool white.
The relative output compared to cool white LEDs in the same series is lower, but not by as much as it used to be. It's not really that great of an issue though, as the blue LEDs will generally make up for any loss in performance, and the advantage of the higher CRI completely outweighs any loss in output and efficiency.
Warm White (2700K-3500K)
While not generally used by themselves as the base white, they are great when used in tandem with higher CCT whites. Warm whites will have very little blue output, lots of red, and very high CRI, with some of them getting up to 98 CRI. These are a great way to add warmth to the light, and improve color rendering in reds, oranges, and pinks without resorting to direct color red LEDs, as they tend to blend far better with the rest of the array.
Direct Color LEDs
Direct color LEDs make up the bulk of the color options available right now for LED setups. The material and doping process for the LED die creates the emission wavelength of the LED without any modifiers, like phosphors that are used in white LEDs. Because there is no down conversion of the energy emitted by the LED die, the efficiency on these LEDs is generally very high. They are very peaky though, meaning they emit light in a very narrow range, and the various color don't overlap a lot. This is the reason that white LEDs are used in conjunction with direct color LEDs, so the valleys between the different wavelengths is filled up, even if it's only a little, depending on the wavelength. We will start low and work up in wavelength.
UV-A (315-400nm)
Ultraviolet light is in the 100nm-400nm range, with UV-A being the 315nm-400nm end of the spectrum. UV-B and UV-C are not even considered here, as they are damaging to tissues. UV-A doesn't get used very often either, but will be found in every fluorescent and gas arc discharge (metal halide, HID) lamp due to the mercury used. Some, including myself have speculated that UV-A can actually be beneficial for coral health and color, but hasn't been proven effectively (at least from what I have seen so far). The big detractor from UV-A LEDs, especially in the 365nm range (mercury spike) has been cost. They are outrageously expensive, and with little known benefit, are generally avoided. UV-A LEDs hovering around the 400nm range aren't really of any use, and the photosynthetic action curve falls off sharply around this point.
As for coloration in the tank, there is very little discernible difference when these are used, as the human eye isn't very sensitive to these wavelengths. When used alone though, they can bring out fluorescent colors that aren't normally seen when using light in the visible spectrum. Due to the potential health risks though, especially regarding the eyes, they aren't recommended for use.
Violet (400-440nm)
Violet LEDs are for growth, not color. Like UV LEDs, the eyes aren't all that sensitive to this light, so the effects when used in conjunction with the primary white and blue LEDs are minimal at best. What they are good at is producing PAR, and lots of it. These are a great way to add growth potential without messing with the color temperature of the light. Caution should be taken with LEDs in this wavelength range, as you can't tell how intense they are, but the corals certainly will. Without proper care, corals can be easily bleached.
Royal Blue (440nm-465nm)
Royal blue LEDs are the muscle used to bring up the color temperature to more reef friendly levels, as well as producing a lot of PAR. They are also one of the best producers of fluorescent colors in corals. Royal blue, compared to blue (or cool blue as some call it) is a deeper color that doesn't illicit the "Windex" look. LEDs in the 440nm range tend to look a little more purple compared to common 450nm-455nm LEDs. When combined with neutral or warm white, the overall light can look a little purple, with the effect exaggerated the lower the CCT of the whites get, and the lower the wavelength of the royal blue LED.
Blue (465nm-485nm)
Blue was initially considered a supplemental color, meaning that it made an effect to the light and coral color, but wasn't really necessary. That's changed though, and it really is a beneficial color that should be used in all arrays, although sparingly.
Blue LEDs do a great job of fluorescing reds and oranges that royal blues just can't touch. They also help to take some of the purple tint out of the light that you can get from a neutral/warm white and royal blue mixture, as well as making the light a little crisper. Too much though, and the tank can look like Windex, so they either need to be used with restraint, or put on a separate channel to be controlled independently.
Cyan/Turquoise (485nm-500nm)
Cyan, or turquoise, is on the falling edge of the large blue photosynthetic peak, so it's not great for growth purposes, but it does have some useful effects on the color of the light and corals. Much like blue, cyan brings out fluorescing colors that other wavelengths don't. they are also good at making the light more crisp, and reducing the purple tint that you can get. It's another color that has to be used sparingly, but it's not as damaging to the color of the light as blue is.
Green (520nm-550nm)
Green does very little other than making the light brighter to the eye, and helping to reduce the purple tint. It really doesn't make anything fluoresce in a way that other colors would, and provides virtually no growth benefit.
Amber (585nm-595nm)
Amber is not used very often, as it doesn't produce much effect. It can help increase color rendering with cool white LEDs, but warmer whites typically have higher amber content anyway, so they don't provide much benefit.
Red-Orange (610nm-620nm)
Red-orange falls into the same boat as amber.
Red (620nm-645)
Red can help with color rendering more than amber and red-orange, as this is the area that most cooler white LEDs are lacking. It's also more in the red photosynthetic peak, so it has some growth benefits. Because our lighting setups are generally more blue heavy though, red can be very distracting when not used properly. Generally, warm white LEDs can be used to better effect to get the same color rendering advantage.
Deep Red (650nm-670nm)
Deep red doesn't have as great of an effect on color rendering as red does, but it can help with very specific color requirements. It was believed to have better growth properties than red, but that idea is starting to fall out of favor. Deep red is being used less and less.
Phosphor Converted Color LEDs
This is a fairly new development in LED technology. These LEDs use a royal blue LED as a base, much like white LEDs, but use selective phosphors to produce a different color. Unlike direct color LEDs though, the output is over a much larger range of wavelengths, and can have some greatly different effects compared to their direct color counterparts.
Lime (566nm-569nm)
566nm-569nm is just the peak wavelength, as these LEDs produce light in the 500nm-620nm range (measured at the 50% output point). The peak wavelength is higher than a typical green, and it actually coincides with the peak human eye sensitivity. This LED was designed with that in mind, as it was intended to help brighten the light, without adversely affecting CCT (something that just green alone can't do). This color can make the light a lot brighter as well as completely eliminate the purple tint that you can get with neutral white and royal blue combinations.
PC Amber (588nm-592nm)
Much like the lime, that's just the peak wavelength. Emitted light ranges from 540nm to 625nm (measured at the 50% output point), and is more intended to help with color rendering without negatively affecting CCT. Much like the lime, it can easily replace amber and red-orange to better effect
Sent from my iPhone using Thor
