Why So Green???

[john.m.cole3]

I've been trying to keep fish and corals alive for almost 2 years now. I've had success and failures. I continue to learn every day. as I stock my tank with different corals, there is definitely a predominance of green amongst my corals. What is the reason for this? Is it the same reason most plants are green?

 

[DracoKat]

following. I am noticing mine are turning green too.

 

[Highgrade]

Green colors in corals usually is related to lighting conditions such as spectrum and intensity(PAR). Iron plays a role in green pigments in corals as well. There are many different factors. What type of corals are you referring to?

 

[DracoKat]

Green colors in corals usually is related to lighting conditions such as spectrum and intensity(PAR). Iron plays a role in green pigments in corals as well. There are many different factors. What type of corals are you referring to?

too much iron, or not enough iron?

 

[nervousmonkey]

too much iron, or not enough iron?

Typically not enough but not always. Iron gets consumed very quickly in a reef tank.

 

[Highgrade]

too much iron, or not enough iron?

Too much, if being consumed too fast I would say you either have a ton of green corals or macro algae consuming the Iron or nuisance algae issues.

 

[saltyfilmfolks]

too much led blue.
https://www.reef2reef.com/threads/lighting-spectra-photosynthesis-and-you.100170/

 

[nervousmonkey]

Interesting Salty. I've never read a paper that showed categorically that pigment ratios in clams were tilted so far to the other side than most of the corals that we keep, except for acros, and even then, the chlorophyll concentrations are even more skewed towards more chlorophyll c. So unless we are lighting up a clam tank, dial the blues down just a bit...

Absorption maximum also occurs much more heavily in the blue to true violet, but no UV, spectrum, so that's really the answer. It's on nature's side to have more pigments that absorb light in the blue spectrum, so more corals will have this coloration, or another way to put it, would be that too much blue will allow that predominant chlorophyll in the zoox to occur.

How could one correct this back to normal? I understand that we could with more white light, and I have actually ordered a MH/T5 combo from ReefBrite, but in an all LED tank, it would make sense to dial in some more 660 nm light as well as 475 nm, 500 nm and 420 nm light. What are you doing since you know this to correct it?

 

[saltyfilmfolks]

Interesting Salty. I've never read a paper that showed categorically that pigment ratios in clams were tilted so far to the other side than most of the corals that we keep, except for acros, and even then, the chlorophyll concentrations are even more skewed towards more chlorophyll c. So unless we are lighting up a clam tank, dial the blues down just a bit...

Absorption maximum also occurs much more heavily in the blue to true violet, but no UV, spectrum, so that's really the answer. It's on nature's side to have more pigments that absorb light in the blue spectrum, so more corals will have this coloration, or another way to put it, would be that too much blue will allow that predominant chlorophyll in the zoox to occur.

How could one correct this back to normal? I understand that we could with more white light, and I have actually ordered a MH/T5 combo from ReefBrite, but in an all LED tank, it would make sense to dial in some more 660 nm light as well as 475 nm, 500 nm and 420 nm light. What are you doing since you know this to correct it?

Ive been having the greening in odd spots on corals that should not have green. Im just going to dial back the time and ratio. this also came up in a few other threads but was just attributed to iron.
fwiw D riddle says growth and color are inverse, its a sunscreen, so if one color is Popping its likely due to overdose of one narrow Nn range. and in today's tanks(and mine) thats the blues for sure.

and if you look at diesels tank hes in the 14k or less range. 20k radium is a broad spread of spectrum. led you can pinpoint a frequency, and make the coral POP.

in mh t5 its less likely a risk.
And Im meeting the OWNER OF REEFBRIGHT ON SATURDAY!!!!!!!!!omgomgomgomg

 

[nervousmonkey]

Wow, you're meeting Curt? How? :jealous:

Dana is a great resource, and it makes sense what he says. Everyone dials in too much blue I think, me included, but doesn't negate the fact that blues are keeping growth from occurring. Seems to me that this all happened because LED's allowed us to dial in a very precise spectrum of light.

Man, ignorance was bliss back in the halide days wasn't it? Didn't know why but they worked, and then people who went from halide to LED kept the same look, or tried to, that they were used to, much more 14 K and lower, than the spectral output we see dialed in on tanks across the globe. If it makes them glow then it must be good, right?

 

[mcarroll]

too much led blue.
https://www.reef2reef.com/threads/lighting-spectra-photosynthesis-and-you.100170/

There are some good articles cited in that thread, but I don't concur with most of the thoughts in the thread itself.

It reads to me like a justification for "full spectrum" as a concept and is trying to leverage the pigment info on corals to do it.

I don't buy it because it doesn't addess how corals (and clams) actually use these pigments nor how they relate to the corals' zooxanthellae.

As an antidote to that link, I would check this out:
“Full Spectrum” – The Internet Reefer’s Decoder Ring

I'll have more coming up there on the subject (new, nerdly posts about every other day in fact), specifically on coral pigments and color, so follow me there if you want to get notified when it posts.

 

[saltyfilmfolks]

There are some good articles cited in that thread, but I don't concur with most of the thoughts in the thread itself.

It reads to me like a justification for "full spectrum" as a concept and is trying to leverage the pigment info on corals to do it.

I don't buy it because it doesn't addess how corals (and clams) actually use these pigments nor how they relate to the corals' zooxanthellae.

As an antidote to that link, I would check this out:
“Full Spectrum” – The Internet Reefer’s Decoder Ring

I'll have more coming up there on the subject (new, nerdly posts about every other day in fact), specifically on coral pigments and color, so follow me there if you want to get notified when it posts.

yea not all but some, its pulling from several sources.
on of my corals was shadoes and hit only with the blue in the shade. it was half green, on a coral that shouldnt be green.

 

[mcarroll]

One source from the upcoming post:
http://plantphys.info/plant_physiology/light.shtml

This is written for plants, but the systems are essentially the same.....function is the same. I like the illustrations of how the pigments actually work....and everything else about the article too, for that matter.

 

[mcarroll]

I like that it shows in chart-form where fluorescence comes from too.

 

[mcarroll]

I've been on that thread since post #16 apparently.

fwiw D riddle says growth and color are inverse, its a sunscreen,

I hate to admit I'm behind on my D. Riddle reading, but I am.

Does this (what I've been reading instead) match hopefully with what he says?

There's:

1. fluorescence from the photosynthetic process
2. non-fluorescent color from the zooxanthellae themselves
3. color from protective pigments
4. color from the coral tissue
5. color from the coral skeleton
6. color from other endosymbionts

The coral animal appears to regulate all of these in concert with their environment....which includes considerations of flow, nutrients and light....(the history of flow, nutrients and light, in fact)

Enhanced color (just like tanning in humans) is in large part a stress response in the face of too much light. (We now know "too much" really isn't all that much.)

We know, separately, that corals recover from injury more slowly when growing quickly vs growing slowly.
Fast Growth May Impair Regeneration Capacity in the Branching Coral Acropora muricata

I'm not sure if that's supportive or contradictory though....the problem with generalizing. (And the reason I'm not done reading!)

 

[john.m.cole3]

Some of this is sinking in. Let me see if I am understanding correctly. For the corals that have their original color as green, it is in mother natures best interest to have many corals this color as they are more responsive to growing through photosynthesis. In our home aquaria corals can shift to to look more green under a more blue spectrum. Sound kind of right so far?

 

[nervousmonkey]

I like the paper Matt, but it's a little misleading, as the terms color and spectrum are used like the same thing, which they are not. To the average every day user, it makes sense to call light from a certain spectrum "blue" or "red", but those are colors. The only thing that "full spectrum" means is that the light basically covers the entire spectrum, which is really misleading, which is also why marketers chose that term, because legally, that's all they are allowed to say about their light without misleading their audience. All that full spectrum means is that they cover 400-700 nm light... So you are correct that it is quite misleading. I like your write-up arguing that full spectrum is really misleading for companies to use, as new reefers have no idea what that means, and they buy crappy lights. :mad:

It isn't quite up to par (no pun intended) to use the "Plant Physiology" paper as anecdotal evidence against the paper from the University of Chicago for a multitude of reasons, primarily that the Plant paper uses chlorophyll B, which just knocks it out of the game when talking corals, clams, etc., as they do not carry this chlorophyll, or I should say, the corals and clams we keep in our tanks do not carry that particular protein.
Secondly, corals and plants both carry different photosynthetic "antenna pigments" as the Plant Phys paper points out. Comparing alpha and beta carotenes, xanthophylls and peridinin in corals and clams is not the same as comparing them in plants. Why? Those are just classifications, which make sense, since corals don't eat carrots.

Essentially, reading the biochemistry of the Plant Phys paper do not show anything about the photosynthetic pathways of the more saltwater loving creatures. Energy transfer in biochemistry has to include the proper pathways to make the results relevant, and the pathways are anything but close to one another.

I agree with you about the link, it only serves to further confuse the topic of "full spectrum", however, the link to the paper contained within that is an academic article simply trying to understand the photosynthetic pigments of corals and clams is pretty clear that the pigments that corals and clams use is quite heavily tilted towards the blue spectrum, and to allow a coloration in the red, or ~ 660 nm spectrum, we need to turn down the blues, otherwise the zooxanthellae that live in those animals will predominate, making the coral appear green, so we need to have the right spectral output, intensity and amount of the light we shine down into our tanks in order to most fully see the natural colors present on the reef, which is what @john.m.cole3 was asking about. Corals will just naturally gravitate to the "green" colors, or combination of 410, 428 and 448 light that emits a green color when activated...

The paper you wrote on lighting was great Matt! Thanks for sharing that, I hope more new reefers read that and understand what you are saying.

 

[nervousmonkey]

Some of this is sinking in. Let me see if I am understanding correctly. For the corals that have their original color as green, it is in mother natures best interest to have many corals this color as they are more responsive to growing through photosynthesis. In our home aquaria corals can shift to to look more green under a more blue spectrum. Sound kind of right so far?

Correct John. There are just way too many pigments in the green colors (not spectrum, just coloration), so not only is it in Mother Nature's best interest, it is unavoidable to find a lot of green corals.

And correct on point number 2 as well, it is very easy for a coral to shift, as they will just host more of the zoox that have green coloration that responds to the "bluer" spectrum of light. Confusing a bit, as color and spectrum are so different, but you have it perfectly.

 

[saltyfilmfolks]

it is unavoidable to find a lot of green corals.

most of the plants on the planet are green so......

 

[john.m.cole3]

Correct John. There are just way too many pigments in the green colors (not spectrum, just coloration), so not only is it in Mother Nature's best interest, it is unavoidable to find a lot of green corals.

And correct on point number 2 as well, it is very easy for a coral to shift, as they will just host more of the zoox that have green coloration that responds to the "bluer" spectrum of light. Confusing a bit, as color and spectrum are so different, but you have it perfectly.

Alright neat. Time to read some of the linked articles now. I'm also thinking about changing my bulb combo now as well. I chose the bulbs based off my previous understanding that more blue=more color and a more white look=faster growth. Now I know it's a bit different than that generalization.