hahnmeister
In Memoriam
Sure sure... no problem.
Coral color, kelvin rating, and growth rates
- Thread starter Echidna09
- Start date
Dana,
Have you done any research with colored films or theatrical gels and sunlight?
I have 2- 4x4' sheets of 3/8" Starphire that I'd like to build a large skylight with, and possibly use gels to "tune" the light for better color.
Do you see any drawbacks?
Thanks for sharing all of your research, and taking time to communicate with those of us with a lot to learn
!
Chris
Have you done any research with colored films or theatrical gels and sunlight?
I have 2- 4x4' sheets of 3/8" Starphire that I'd like to build a large skylight with, and possibly use gels to "tune" the light for better color.
Do you see any drawbacks?
Thanks for sharing all of your research, and taking time to communicate with those of us with a lot to learn
!Chris
MCsaxmaster
New member
There are other reasons that colorful corals could have a lower electron transport rate (as demonstrated by various researchers).
Fabricius showed that colorful corals retain less heat than colorful ones. Does this play any role at all? No one to my knowledge has connected the dots on this one.
The zooxanthella clade could play a difference - some adjust to light intensity by adjusting their numbers, some adjust the PSU size. Some are heat or bleaching resistant due to the chemical compostion of the thyllakoid membranes. Color might have nothing to do with their photosynthetic capacity.
Sure, I would never argue that we are at all certain about what these proteins do or how exactly they do it.
A friend was meaning to work on the effects of colony pigmentation on sensitivity of the zoox. to temperature stress, but I'm not sure how much she's been able to get done with that. Darker or more colorful colonies do tend to be warmer than lighter or unpigmented colonies, and that microtemperature could exert selective pressure against those colored corals during high temperature stress, as suggested by work from Fabricius et al.
The bulk of my friend's work deals with looking at differences in susceptibility to temp stress and connecting that to differences in thylakoid membrane composition (and hence fluidity).
Generally zoox. make adjustments for differences in light intensity by changing PSU size and pigment density, but not by changing their density within the coral. That would increase shading on each zooxanthella--how could that be used as a mechanism to reduce light limitation? Besides, many studies have shown that zoox. density is similar over a range of depths in a given coral.
But having said all of this, I still don't see any reason that we should think light spectrum incident on the corals should affect the production of pigments that we agree may or may not have anything to do with the fact that they interact with light.
Smarty pants ;-). The point is that spectrum is often an important part of photochemical responses. I don't have time to pick through the references, so I'll cut-and-paste a partial list - there are some real gems buried in the biomedical literature!
Ha,
Yes, spectrum can play a part in biochemical responses, but only when spectrum is an important factor in the functioning of these processes.
For example, there's no reason that insulin production in our body should be affected by the color our eyes see. There would be no benefit to doing so. On the other hand, there IS benefit to detecting increases in UVR and UVR damage. Thus, when exposed to increased UVR, we tan.
I'll take a look through that lit. list when I get a chance.
Chris
Fabricius showed that colorful corals retain less heat than colorful ones. Does this play any role at all? No one to my knowledge has connected the dots on this one.
The zooxanthella clade could play a difference - some adjust to light intensity by adjusting their numbers, some adjust the PSU size. Some are heat or bleaching resistant due to the chemical compostion of the thyllakoid membranes. Color might have nothing to do with their photosynthetic capacity.
Sure, I would never argue that we are at all certain about what these proteins do or how exactly they do it.
A friend was meaning to work on the effects of colony pigmentation on sensitivity of the zoox. to temperature stress, but I'm not sure how much she's been able to get done with that. Darker or more colorful colonies do tend to be warmer than lighter or unpigmented colonies, and that microtemperature could exert selective pressure against those colored corals during high temperature stress, as suggested by work from Fabricius et al.
The bulk of my friend's work deals with looking at differences in susceptibility to temp stress and connecting that to differences in thylakoid membrane composition (and hence fluidity).
Generally zoox. make adjustments for differences in light intensity by changing PSU size and pigment density, but not by changing their density within the coral. That would increase shading on each zooxanthella--how could that be used as a mechanism to reduce light limitation? Besides, many studies have shown that zoox. density is similar over a range of depths in a given coral.
But having said all of this, I still don't see any reason that we should think light spectrum incident on the corals should affect the production of pigments that we agree may or may not have anything to do with the fact that they interact with light.
Smarty pants ;-). The point is that spectrum is often an important part of photochemical responses. I don't have time to pick through the references, so I'll cut-and-paste a partial list - there are some real gems buried in the biomedical literature!
Ha,
Yes, spectrum can play a part in biochemical responses, but only when spectrum is an important factor in the functioning of these processes.For example, there's no reason that insulin production in our body should be affected by the color our eyes see. There would be no benefit to doing so. On the other hand, there IS benefit to detecting increases in UVR and UVR damage. Thus, when exposed to increased UVR, we tan.
I'll take a look through that lit. list when I get a chance.
Chris
hahnmeister
In Memoriam
<a href=showthread.php?s=&postid=11144810#post11144810 target=_blank>Originally posted</a> by H20ENG
Dana,
Have you done any research with colored films or theatrical gels and sunlight?
I have 2- 4x4' sheets of 3/8" Starphire that I'd like to build a large skylight with, and possibly use gels to "tune" the light for better color.
Do you see any drawbacks?
Thanks for sharing all of your research, and taking time to communicate with those of us with a lot to learn
Chris
Ive done that actually. In Chicago, a 8'x8' 1500g tank with a 6x6 area of skylights over it. I used 3x 12"x72" strips (a 36x72 sheet) of transparent blue acrylic to filter 1/2 the light coming through the skylight... very effective. Sure, it cuts down the total output, but its not like it matters... its a huge skylight! Otherwise, the 40-some blue and actinic T5 bulbs over the edges of the tank fill in the rest.
RiddleLabs
New member
Aloha H2OENG-
I have done some work with gels and filters, mostly with calculating which filter to use to give a desired result.
There is a formula to determine affects of filters on the ultimate Kelvin Rating and is called the Mired Shift Value. It is:
1,000,000 - 1,000,000 = Mired Shift Value
Desired Kelvin Rating Lamp Kelvin Rating
Example:
Determine the Mired Shift Value to alter Kelvin Rating from 3,200°K to 20,000°K:
1,000,000 - 1,000,000 = 50 â€"œ 313 = - 263
20,000 3,200
In this case, a Roscoluxâ"žÂ¢ Double Blue Filter #3220 will give the desired result. Mired Shift Values are an industry standard; determine the Mired Shift Value and contact a theatrical supply house for advice for the correct filter in other applications.
Probably better to use colored acrylic than gels.
Dana
I have done some work with gels and filters, mostly with calculating which filter to use to give a desired result.
There is a formula to determine affects of filters on the ultimate Kelvin Rating and is called the Mired Shift Value. It is:
1,000,000 - 1,000,000 = Mired Shift Value
Desired Kelvin Rating Lamp Kelvin Rating
Example:
Determine the Mired Shift Value to alter Kelvin Rating from 3,200°K to 20,000°K:
1,000,000 - 1,000,000 = 50 â€"œ 313 = - 263
20,000 3,200
In this case, a Roscoluxâ"žÂ¢ Double Blue Filter #3220 will give the desired result. Mired Shift Values are an industry standard; determine the Mired Shift Value and contact a theatrical supply house for advice for the correct filter in other applications.
Probably better to use colored acrylic than gels.
Dana
RiddleLabs
New member
Aloha Hahnmeister,
Its a bit like this... when Home Depot was changing all their halides out for T5s, at the 50/50 point, you could look into the halide section of the store, and things were bright, sure, but 'duller' in a way. When I looked at the T5 lit side, all the colors seemed to 'pop' more, esp the bright orange color on all the racking... almost like with a blacklight... but these are all 3000K and 6500K GE bulbs.
There are several possibilities.
1. The T5 lamps produce more warm wavelengths (they are 3000 and 6500K lamps, correct?), and the warmer colors are simply better showcased under this spectrum.
2. The paint Home Depot uses has a fluorescent additive, as do some of the inks on product packaging to make them immediately visually appealing. Perhaps the spectrum of the T5’s excited these fluorescent pigments, did not ‘wash them out’ or a combination of both.
3. The metal halide lamps were horrible (spectrally-speaking) and tended to make everything appear dull.
I have observed similar things with T5s in the home reef as well. It seems that there is something in the light spectrum that allows corals to color up better than with halides, even when under lower light levels for some otherwise light-greedy acros.
Obviously we have changed gears here, and are talking biochemical responses to a stimulus. I suspect some of the coloration you’re seeing is due to coral pigments NOT bleaching. It is quite common for some corals to lose pigmentation if there is too much light, or if the photoperiod is too long.
The pigments arent just picked up by the T5s in some way for how I see them, but they change all together. I can get orange whorling cap to color up into a neon red color, and Blue tortuosa to light up this way as well.
The orange caps will turn pastel orange if bleached (in this case, probably due to loss of photopigments). By the same token, the increase of zoox (or their photopigments) as a result of lower light intensity can cause the coral to take on a different color â€"œ usually a deep orange or reddish-orange).
And it wasnt just because of variation in spectrum.
Agreed â€"œ I think the coloration responses are due to intensity (but I have a lot of spec work to do before making a flat statement).
I can literally grow corals faster and with better coloration with T5s than with halides. I thought that with my new halide + T5 combo, I would get this still, if not more... but this just isnt so. Just wondering if there is some explaination for this.
The same result can be had with LEDs. I think we’re observing results of a hospitable environment for pigments (no photo-bleaching, which can cause ‘pasteling’ of colors). At the same time, lower light intensity is causing a shift in zoox photopigments or cell density, which of course changes the reflectance pattern.
You’ve got a PAR meter, don’t you? Some intensity numbers could help us nail this down.
Dana
Its a bit like this... when Home Depot was changing all their halides out for T5s, at the 50/50 point, you could look into the halide section of the store, and things were bright, sure, but 'duller' in a way. When I looked at the T5 lit side, all the colors seemed to 'pop' more, esp the bright orange color on all the racking... almost like with a blacklight... but these are all 3000K and 6500K GE bulbs.
There are several possibilities.
1. The T5 lamps produce more warm wavelengths (they are 3000 and 6500K lamps, correct?), and the warmer colors are simply better showcased under this spectrum.
2. The paint Home Depot uses has a fluorescent additive, as do some of the inks on product packaging to make them immediately visually appealing. Perhaps the spectrum of the T5’s excited these fluorescent pigments, did not ‘wash them out’ or a combination of both.
3. The metal halide lamps were horrible (spectrally-speaking) and tended to make everything appear dull.
I have observed similar things with T5s in the home reef as well. It seems that there is something in the light spectrum that allows corals to color up better than with halides, even when under lower light levels for some otherwise light-greedy acros.
Obviously we have changed gears here, and are talking biochemical responses to a stimulus. I suspect some of the coloration you’re seeing is due to coral pigments NOT bleaching. It is quite common for some corals to lose pigmentation if there is too much light, or if the photoperiod is too long.
The pigments arent just picked up by the T5s in some way for how I see them, but they change all together. I can get orange whorling cap to color up into a neon red color, and Blue tortuosa to light up this way as well.
The orange caps will turn pastel orange if bleached (in this case, probably due to loss of photopigments). By the same token, the increase of zoox (or their photopigments) as a result of lower light intensity can cause the coral to take on a different color â€"œ usually a deep orange or reddish-orange).
And it wasnt just because of variation in spectrum.
Agreed â€"œ I think the coloration responses are due to intensity (but I have a lot of spec work to do before making a flat statement).
I can literally grow corals faster and with better coloration with T5s than with halides. I thought that with my new halide + T5 combo, I would get this still, if not more... but this just isnt so. Just wondering if there is some explaination for this.
The same result can be had with LEDs. I think we’re observing results of a hospitable environment for pigments (no photo-bleaching, which can cause ‘pasteling’ of colors). At the same time, lower light intensity is causing a shift in zoox photopigments or cell density, which of course changes the reflectance pattern.
You’ve got a PAR meter, don’t you? Some intensity numbers could help us nail this down.
Dana
hahnmeister
In Memoriam
Okay, I have a pink prostrata with blue tips. This is the best example. I would have to keep it under at least 300, if not 400+ microMol/m2/s of light with halides for it to color up. If I put it in 250 or less, it would 'brown out'.
Under T5s, it was under 350 at most... at the very tips, and sometimes it was on the sand... and it turned neon.
With the orange cap, funny you should mention... Since the new tank with the light mover, I put the deep neon blood red cap in a corner so it wouldnt bleach out or anything. Flow was pretty constant as it was in the 'backwash' from a Tunze stream. Anyways, it started to bleach out from the center/bottom out. The light level in the corner it was in was 100-180 (depending on light mover). I had to move it up the side of a rock, so it would get 400+ when the halide came over it. Now its coloring in darker and quickly regrowing... reverse of what I thought.
I too was thinking the corals were coloring in better due to lower light, but if I tried lower light with the halides, the corals just faded, and sometimes bleach.
Under T5s, it was under 350 at most... at the very tips, and sometimes it was on the sand... and it turned neon.
With the orange cap, funny you should mention... Since the new tank with the light mover, I put the deep neon blood red cap in a corner so it wouldnt bleach out or anything. Flow was pretty constant as it was in the 'backwash' from a Tunze stream. Anyways, it started to bleach out from the center/bottom out. The light level in the corner it was in was 100-180 (depending on light mover). I had to move it up the side of a rock, so it would get 400+ when the halide came over it. Now its coloring in darker and quickly regrowing... reverse of what I thought.
I too was thinking the corals were coloring in better due to lower light, but if I tried lower light with the halides, the corals just faded, and sometimes bleach.
RiddleLabs
New member
Hahnmeister,
>>Okay, I have a pink prostrata with blue tips. This is the best example. I would have to keep it under at least 300, if not 400+ microMol/m2/s of light with halides for it to color up. If I put it in 250 or less, it would 'brown out'.<<
You're saying it lost pink color? Blue color? Both?
>>Under T5s, it was under 350 at most... at the very tips, and sometimes it was on the sand... and it turned neon.<<
Neon - meaning green fluorescence? Which T5s are you using? I did a lot of T5 work for Sunlight Supply years ago. That data is on the Conscientious Aquarist site. It would be interesting look at your spectral quality.
>>With the orange cap, funny you should mention... Since the new tank with the light mover, I put the deep neon blood red cap in a corner so it wouldnt bleach out or anything. Flow was pretty constant as it was in the 'backwash' from a Tunze stream. Anyways, it started to bleach out from the center/bottom out. The light level in the corner it was in was 100-180 (depending on light mover). I had to move it up the side of a rock, so it would get 400+ when the halide came over it. Now its coloring in darker and quickly regrowing... reverse of what I thought.<<
Did we calculate the light dosage on this 'mover', maybe a year ago? I'd like to re-visit the intensity numbers again.
Thanks-
Dana
>>Okay, I have a pink prostrata with blue tips. This is the best example. I would have to keep it under at least 300, if not 400+ microMol/m2/s of light with halides for it to color up. If I put it in 250 or less, it would 'brown out'.<<
You're saying it lost pink color? Blue color? Both?
>>Under T5s, it was under 350 at most... at the very tips, and sometimes it was on the sand... and it turned neon.<<
Neon - meaning green fluorescence? Which T5s are you using? I did a lot of T5 work for Sunlight Supply years ago. That data is on the Conscientious Aquarist site. It would be interesting look at your spectral quality.
>>With the orange cap, funny you should mention... Since the new tank with the light mover, I put the deep neon blood red cap in a corner so it wouldnt bleach out or anything. Flow was pretty constant as it was in the 'backwash' from a Tunze stream. Anyways, it started to bleach out from the center/bottom out. The light level in the corner it was in was 100-180 (depending on light mover). I had to move it up the side of a rock, so it would get 400+ when the halide came over it. Now its coloring in darker and quickly regrowing... reverse of what I thought.<<
Did we calculate the light dosage on this 'mover', maybe a year ago? I'd like to re-visit the intensity numbers again.
Thanks-
Dana
hahnmeister
In Memoriam
The prostrata is pink with blue tips, and yes, when it loses color, the whole corals just turns brown.
Where the orange cap is now, its PAR is at a minimum 200, and maxes out at over 400... so its average is something in between... 300? This is waaay more than normal it seems.
It makes me wonder if the time under the T5s chaged the coral in some way besides color. This one seems adapted to much higher lighting levels than the other colony I have sitting on the sand. If I give that one too much light, it starts to fade/bleach. I have to keep it under 200 or less.
Where the orange cap is now, its PAR is at a minimum 200, and maxes out at over 400... so its average is something in between... 300? This is waaay more than normal it seems.
It makes me wonder if the time under the T5s chaged the coral in some way besides color. This one seems adapted to much higher lighting levels than the other colony I have sitting on the sand. If I give that one too much light, it starts to fade/bleach. I have to keep it under 200 or less.
dachsieholic
New member
corals and lighting
corals and lighting
Very interesting thread!
corals and lighting
Very interesting thread!
Similar threads
