Coral Questions1 - Light and Colors

[Tinnerito]

Hello! I get recommend quite a few sw aquarium videos on social media, and most of the videos recommended to me are macroalgae tanks. But a lot of them I see have corals. More commonly leather corals if that's inmportant at all. But whats confusing is that those content creators, and likely some of you reading this use ordinary aquarium plant lights, or macroalgae lights for those tanks. How come they're able to grow coral? I'm told that corals need dozens of colors from deep blue to UV and all of this complicated stuff yet all of these plant lights have only white, green, red, and sometimes blue. Can somebody explain? Am I viewing light all wrong?

 

[corosato]

the blue you see in a lot of reef tanks is to make the fluorescence pop, but a lot of those soft corals in the macro algae tanks look better under white light than blue light as they do not have that much of the fluorescence. All corals use "full spectrum" lighting for photosynthesis and some grow better under it, just some corals tend to look very brown under that and a lot of reefers prefer the pop that the blue lights give. My tank runs full spectrum half the day and then blues only half the day just for viewing. obviously YMMV, as some species of corals prefer lower light as they are found deeper in the water.

standard "I am not an expert just a guy on a forum" disclaimer :)

 

[JTP424]

Agreed with above. If you think about corals in the ocean, they're getting everything they need from the sun.
so match sun par and "channels" and you should be able to grow corals.
Below is an example of the pop between more white lights, and more poppy blues.
The left looks "dingy" in spots etc, where the right looks "cleaner"

 

[corosato]

zoas are always the best way to show this lol. My wife thinks they are ugly until the blues kick in.

 

[BryanM]

People also sometimes run blues only to try and reduce algae growth. I'd be in the camp lately, though I intend to go back to a mix eventually

 

[Tinnerito]

the blue you see in a lot of reef tanks is to make the fluorescence pop, but a lot of those soft corals in the macro algae tanks look better under white light than blue light as they do not have that much of the fluorescence. All corals use "full spectrum" lighting for photosynthesis and some grow better under it, just some corals tend to look very brown under that and a lot of reefers prefer the pop that the blue lights give. My tank runs full spectrum half the day and then blues only half the day just for viewing. obviously YMMV, as some species of corals prefer lower light as they are found deeper in the water.

standard "I am not an expert just a guy on a forum" disclaimer :)

Agreed with above. If you think about corals in the ocean, they're getting everything they need from the sun.
so match sun par and "channels" and you should be able to grow corals.
Below is an example of the pop between more white lights, and more poppy blues.
The left looks "dingy" in spots etc, where the right looks "cleaner"

Well thank goodness because unpopular opinion: I've never been a fan of how corals look under that deep blue light because it takes away from their beauty in the natural state, even if it means theur colors are less saturated. Thanks for the replies! I'm another step closer to buying a coral again, and will probobaly never spend 264 usd on a light again.

So...does this mean an ordinary light that works on plants would theoretically grow coral?? (with more algae growth, and less coral coloration accounted for)

 

[Tinnerito]

zoas are always the best way to show this lol. My wife thinks they are ugly until the blues kick in.

Ugly? How they look under natural light is what made me want them once but their bright overwhelming colors under blue light made me not like them as much.:worried-face:

 

[corosato]

Ugly? How they look under natural light is what made me want them once but their bright overwhelming colors under blue light made me not like them as much.:worried-face:

nothing wrong with that, everyone is different. there are definitely zoas that look better under whites to me than blues as well, I have some gorgeous blue ones that just get lost in blue light, but when the lights are white they are one of my favs.

 

[Tinnerito]

Agreed with above. If you think about corals in the ocean, they're getting everything they need from the sun.
so match sun par and "channels" and you should be able to grow corals.
Below is an example of the pop between more white lights, and more poppy blues.
The left looks "dingy" in spots etc, where the right looks "cleaner"

Does this mean a normal full spectrum plant light would grow coral? What "necessary" colors exactly am I looking for? I personally don't like how these expensive coral lights look anyway.

 

[JTP424]

So I was correct and incorrect.
In the ocean light penetrates water at different depths, so the reds/oranges/yellows etc typically get filtered out the deeper you go, so corals in the "wild" get more blues the deeper they go.
On the reverse, you can't run full time blues as they don't provide the corals with enough of the light spectrum as they DO need full spectrum :)

Full spectrum should work, you'll run into nuisance algae issues as turning down the reds/greens/whites (which result in more blue) is typically done to avoid (as stated above by @BryanM )

Just make sure your light has enough PAR (oomph)