Can I keep a mixed reef at 6500k lighting?

[anthony1222]

I HATE blue lights for reef tanks so I want to keep my reef at 6500k lighting because it mimics the color of daylight and is more true to actual coral reefs but I don't know if it'll hurt the coral. Most pro reefers use bluer light for some reason so that's why Im asking this question.

I'm planning on keeping mostly LPS like euphyllias and SPS like birds nests. I have a radion g6 pro.

 

[Troylee]

Nothing wrong with 6500k! It’s full spectrum and grew corals like weeds when we used the old skool metal halides.. I still run metal halides but I use 14k which is white with a slight blue tint.

 

[FUNGI]

I used to run 6500K MH's when I first started and they are the best for coral growth. Nothing wrong with running 6500K....

 

[anthony1222]

Nothing wrong with 6500k! It’s full spectrum and grew corals like weeds when we used the old skool metal halides.. I still run metal halides but I use 14k which is white with a slight blue tint.

If lower kelvin grows coral faster then why do people use bluer lights? For coral fluorescents?

 

[buruskeee]

If lower kelvin grows coral faster then why do people use bluer lights? For coral fluorescents?

Corals are used to blue light from the ocean water filtering out the higher spectrum. All light will grow though.

 

[Troylee]

If lower kelvin grows coral faster then why do people use bluer lights? For coral fluorescents?

Because somebody fashioned the statement “white lighting grows algae” and yes the colors are drab under 6500k compared to blue lighting. Farmers grow under 6500k then color up under blue lighting before selling.

 

[anthony1222]

Because somebody fashioned the statement “white lighting grows algae” and yes the colors are drab under 6500k compared to blue lighting. Farmers grow under 6500k then color up under blue lighting before selling.

Can I use 6500k throughout the day and have a blue period like at around 20000k at sunset to show off the coral colors or would that stress out the coral

 

[Troylee]

Can I use 6500k throughout the day and have a blue period like at around 20000k at sunset to show off the coral colors or would that stress out the coral

Completely fine.. I run xho reefbrites for 12 hours a day “blue only” and my halides for 6 hours at noon.

 

[FUNGI]

Can I use 6500k throughout the day and have a blue period like at around 20000k at sunset to show off the coral colors or would that stress out the coral

That would not stress then out.....use blue in am and then pm....sunrise/sunset effect

 

[Narideth]

I have my tanks all set for a 5-6 hr full spectrum period dimming down to only blues for 2 hrs in the evening. Everything seems to love it and I get to not only see my lovely happy clams under whites but the poppy trippy florescence under blues.

 

[Spare time]

As long as you have the required blues, it doesn't matter. The only thing is not to have an extreme amount of red but that would be difficult imo since most reef lights have very little red.

 

[anthony1222]

As long as you have the required blues, it doesn't matter. The only thing is not to have an extreme amount of red but that would be difficult imo since most reef lights have very little red.

Lowering the kelvin reduces the percentage of blues. Is that correlating to color or spectrum

 

[anthony1222]

Completely fine.. I run xho reefbrites for 12 hours a day “blue only” and my halides for 6 hours at noon.

This schedule seems ok? 2 hours of 20000k in the morning and sunset and around 6 hours of 6500k during daytime

 

[FUNGI]

I would do 1 hour sunrise(blue only), 8 hours 6500K, 1 hour sunset(blue only) 10 hours total light.
Put everything on a timer (unless you have a controller)....

 

[FUNGI]

As long as you have the required blues, it doesn't matter. The only thing is not to have an extreme amount of red but that would be difficult imo since most reef lights have very little red.

Not sure what you mean by "the required blues"?

 

[anthony1222]

I would do 1 hour sunrise(blue only), 8 hours 6500K, 1 hour sunset(blue only) 10 hours total light.
Put everything on a timer (unless you have a controller)....

I control it using the mobius app so it’s all automatic. Here’s the new schedule ( Ramps up to 1 hour blue, then 8 hours white, then 1 hour blue and it ramps down to moonlighting to off)

 

[FUNGI]

Didnt know you had Moius and thus (I'm just being anal)......30 minutes (within sunrise/sunset) have 50/50 mix of blue and 6500K.....thats would be a perfect mix IMO....great transitions.....

 

[ISpeakForTheSeas]

Lowering the kelvin reduces the percentage of blues. Is that correlating to color or spectrum

If it reduces the percentage of blue light put out by the fixture, then the color and PAR output of the light would be impacted.

The color temperature (measured in Kelvin) tells us how warm (red)/cool (blue) a "white" light looks to our eyes.

The spectrum (i.e. the wavelength of light produced) is the actual color of the light(s) produced by the light fixture (for example, a 395nm light emitting diode by itself produces a violet light) - how it looks to our eyes changes depending on all the colors that are produced at one time. For example, if you take a blue light diode (that only produces blue light by itself) and add some yellow, red, and green diodes to it all in one fixture, the light produced by the fixture would appear some variation of white to us (what variation would depend on how much of each light color is in the blend). The more blue added/other colors subtracted, the cooler the light; the more other colors (red, yellow, green, etc.) added/blue subtracted, the warmer the light.

So, the wavelengths and the actual amounts of light put out (measured for coral-keeping purposes as PAR - Photosynthetically Active Radiation) by each light-producing piece of a light fixture (in LED's the light producing pieces are the Light Emitting Diodes themselves) impacts the color temperature of the light as a whole.

All that to say that by decreasing the percentage of blue light the light fixture is putting out, you would change the color temperature (by removing blue light to make the color warmer), and you would reduce the amount of light (PAR) put out by the fixture as well.

Not sure what you mean by "the required blues"?

I think they're talking about the amount and wavelength of blue light needed to help the corals thrive photosynthetically. Long story short, coral zooxanthellae (and other kinds of algae) use certain kinds of light to produce energy for themselves and their host coral; certain wavelengths of blue light hit a photosynthesis "peak" that helps the zooxanthellae produce the highest amount of energy possible. Without enough blue light from around that peak wavelength, it could be tough for a coral's zooxanthellae to produce enough energy to help the coral thrive.


Also, for the OP, "white" light (6500K and others) can definitely grow corals if they produce the right wavelengths of light in the right quantities.

Blue light has been shown with deeper water corals to help them calcify (i.e. grow) faster in aquariums, but shallower water corals (like many of the ones we keep) can grow faster under white (i.e. full-spectrum) light. Which kind of light is better for a specific coral depends on a number of different factors (wild or captive, the type and amount of light it's used to, how long it has to adjust to different lighting, etc.), but both blue light and white light work fine.

White (full-spectrum) light (with some red light mixed in) is better for photosynthesis, as various photosynthetic pigments have "peaks" in various different light wavelengths (blue, green, red, etc.). The main peaks for both coral zooxanthellae, other types of algae, and plants are typically in the blue and red light wavelengths. Despite zooxanthellae having a peak in the red light wavelengths, however, corals don't like getting too much red light (in at least some cases, they actually actively avoid red light as larvae when they go to settle, and too much red light can kill otherwise healthy corals in aquariums over a long enough time).

These two paragraphs above get at two of the three main reasons why people run just blue lights: 1 - they believe it will help their coral grow faster (it might, dependent on the circumstances of the individual coral), 2 - (like Troylee mentioned above) they believe it will prevent algae growth/give coral an edge over algae in the tank (this is dubious, but it's possible there might be a very small impact of this nature), and 3 - they want their corals to fluoresce more (this one is definitely accurate; fluorescent colors will "pop" more to our eyes under heavy blue/violet light - think glowsticks under blacklight for comparison).

So, if you don't like the look of the heavy blue light, by all means, run white light - your tank will be just fine. Just be aware that changes to your lighting can impact your coral (and fish) color, health, and growth: if the corals are adapted long-term to heavy blue lighting (which may be the case if they've been in a blue-light tank for a while or if they're from deep waters), they will eventually adapt to the new lighting, but you might see some slowed growth, dulled color, and less polyp extension during the adjustment period. If you want to ease them into the transition, then running just blue light for an hour or so in the morning and/or evening as suggested above may help, but I honestly doubt it would be necessary.

(If this block of text didn't scare you off and you want to read more on light and algae/coral, I have links available).

 

[FUNGI]

 

[Spare time]

Not sure what you mean by "the required blues"

Zooxanthellae needs some blue light to thrive, so really as long as you provide that, it doesn't matter. My point was supposed to be that that 6500k is fine.