Red Light - Good or Bad for Corals?

[Straight.Reefin]

I run red at 14 on the radions, but 24 would be my max. That’s based on sps ab+ schedule by Ecotech

A lot run it like that and I run mine maxing out at 55% for 13.5 k and my acros are doing great and as I put in here earlier, Sanjay joshi runs his at 100%

 

[Lasse]

One thing to stress if people start to run their reds a little bit more than before. Beware of low Kelvin whites - the have a lot of red wavelengths. I run a lot of reds - but I do not use white LEDs at all. I´m going to change my lighting soon. The new fixture will content RGB LEDs - probably I will run the white very low but the RGB at 100 %

Sincerely Lasse

 

[taricha]

This line of reasoning seems to imply that coral under sunlight with some red filtered out would outperform coral in straight sunlight.
Improved spectrum by subtraction?
Counter -intuitive, but seems to follow from this logic.

 

[Straight.Reefin]

One thing to stress if people start to run their reds a little bit more than before. Beware of low Kelvin whites - the have a lot of red wavelengths. I run a lot of reds - but I do not use white LEDs at all. I´m going to change my lighting soon. The new fixture will content RGB LEDs - probably I will run the white very low but the RGB at 100 %

Sincerely Lasse

Do you know if the cool white or warm whites on radions have a lot of red wavelengths in them by any chance?

 

[Lasse]

Nope. If you know the type of LED - you probably can look up a spectral graph. Warm whites normally have a lot of red

Sincerely Lasse

 

[Straight.Reefin]

Nope. If you know the type of LED - you probably can look up a spektra graph. Warm whites normally have a lot of red

Sincerely Lasse

Okay thanks! And that definitely makes sense because when I turn the warm whites up it definitely gives off a color like the reds do when they get turned up also

 

[Sallstrom]

No red is not bad as long as it's not too much(or just red). We have had a couple of corals(Seriatopora) that has survived under just 660nm(red) for a couple of month now(for an experiment). But they doesn't look like corals you want in your tank, they are almost white
How much red is too much? I don't know.

/ David

We did some measurements today of the corals that's been under 660 nm and 660+420 nm. We started 12/01/2018(12th January) and the experiment goes on a bit longer because my colleague want to try oxygen production in the corals from the different treatments.
Red light was PAR 75 at the egg crate where the corals where on. 95 PAR at the surface. Red+blue was measured to 50% each, with the same total PAR as the red.

Here are some examples of how some of the corals looked today. Starting from the left, 1-3 only red, 4-6 red+blue.

Seriatopora hystrix Green

Seriatopora hystrix red version

Acropora nana

Will get back when we have more results

Edit. Check the polyps on the red Seriatopora hytrix, they are on the shadow side on the coloies thats been under red only!

 

[Brew12]

Edit. Check the polyps on the red Seriatopora hytrix, they are on the shadow side on the coloies thats been under red only!

Fascinating!

I've also noticed that I have very poor polyp extension on my system but that it is often better on the shadow side of my corals. ;Writing

 

[Lasse]

I assume they was nearly the same size when you start the experiment.

Sincerely Lasse

 

[Sallstrom]

I assume they was nearly the same size when you start the experiment.

Sincerely Lasse

Yes. I have pictures somewhere in my computer And the weight on the three species of Seriatopora. Some of the colonies in red+blue have more than doubled their weight in 6 months!

 

[Lasse]

You should run one with only blue too

Sincerely Lasse

 

[Sallstrom]

You should run one with only blue too

Sincerely Lasse

Yes. But in this case it was more an experiment to see if a coral would survive with only red and if blue and red gave a better result(e.g. If blue "helpes protect " from red).
Check with Björn if you want to see the data @Lasse(its on Dropbox) I'm trying to get into holiday mode

 

[Lasse]

I'm trying to get into holiday mode

For all that´s do not know - it is the midsummer eve tomorrow. The day of the Swedish bottle! If you come here this day - you will have problem to see any sober person and if you arrive to a city - probable do not see any at all. The most loved holyday before it comes - the most hated the day after!

Midsummer for dummies



I´m borne 11 of march

Sincerely Lasse

 

[mcarroll]

Thank you for continuing to post updates on this!!

 

[Tristren]

Edit. Check the polyps on the red Seriatopora hytrix, they are on the shadow side on the coloies thats been under red only!

That really is fascinating!

Yes. I have pictures somewhere in my computer And the weight on the three species of Seriatopora. Some of the colonies in red+blue have more than doubled their weight in 6 months!

Same size but doubled their weight?

Thanks for posting this.

 

[Sallstrom]

That really is fascinating!



Same size but doubled their weight?

Thanks for posting this.

Thanks!

No, they all started about the same sizes all six specimen. The ones under red+blue have grown both size and weight. The ones under only red has grown as well, but not much at all.

/ David

 

[Sallstrom]

Some more observations in our experiment.

The Echinopora sp did not survive under only red (N=3). 100% survival under red+blue.
Stylophora pistillata had not great survival under any of the light treatments. About 33-50%.
Same with another Acropora sp "green slimer " - 33 % under both light treatments(AEFW?).
We lost one Acropora nana, probably an urchin who moved it somewhere

All three Seriatopora species and Acropora nana had almost 100 % survival.

So it seems to be different results for the different species. But it's still only three specimen of each species in each treatment, so I'm not sure it's possible to say much at all

We only did measurement on the three Seriatopora species (weight). The others were just for survival and colour observation.

/ David

 

[Tristren]

Thanks!

No, they all started about the same sizes all six specimen. The ones under red+blue have grown both size and weight. The ones under only red has grown as well, but not much at all.

/ David

Ok, I thought you were saying they had become denser over the period, which would have been an interesting finding as well

 

[mcarroll]

So it seems to be different results for the different species. But it's still only three specimen of each species in each treatment, so I'm not sure it's possible to say much at all

It's possible to say this is very interesting and that it's worthy of continued reporting and investigation.

 

[Tristren]

Some more observations in our experiment.

The Echinopora sp did not survive under only red (N=3). 100% survival under red+blue.
Stylophora pistillata had not great survival under any of the light treatments. About 33-50%.
Same with another Acropora sp "green slimer " - 33 % under both light treatments(AEFW?).
We lost one Acropora nana, probably an urchin who moved it somewhere

All three Seriatopora species and Acropora nana had almost 100 % survival.

So it seems to be different results for the different species. But it's still only three specimen of each species in each treatment, so I'm not sure it's possible to say much at all

We only did measurement on the three Seriatopora species (weight). The others were just for survival and colour observation.

/ David

What's particularly interesting for me is the polyps on the red Seriatopora. It perfectly demonstrates for the rest of us, what you're asking about.

If there was just a difference in overall growth it would show that corals need blue light to grow (which, yeah). But this really shows that these corals really don't like the red light. At least not this amount of red light in the absence of other light...