LIght Intensity (PAR) and Tridacna Clams

J1a

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Just give it plenty of light and make sure you see new shell growth underneath the mantle. Those changes are probably from a different spectrum of light or how the light is hitting the clam. Also, clams have the ability to move or change where the zooxanthellae reside in their mantles. Zooxanthellae aren't the only thing that produces pigment in the mantle.
I believe these are all true. However, it seems that while there are plenty of discussion on how acroporidae can "color up", there is little discussion on color morphing of clams.

If we can induce clams to develop higher contrast patterns, or to produce more iridophores, that would really be awesome. (At this stage, I think it's possible)
 
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minus9

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I believe these are all true. However, it seems that while there are plenty of discussion on how acroporidae can "color up", there is little discussion on color morphing of clams.

If we can induce clams to develop higher contrast patterns, or to produce more iridophores, that would really be awesome. (At this stage, I think it's possible)
They won't change like corals change, but they may lean towards one color or another or those colors will darken or lighten with different light/spectrum, etc... They will establish their zooxanthellae density when they are extremely small, which goes unchanged for most of their lives, but as they age, they will actually lose some of the zooxanthellae. James Fatherree talks about this in his book.
 

J1a

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They won't change like corals change, but they may lean towards one color or another or those colors will darken or lighten with different light/spectrum, etc... They will establish their zooxanthellae density when they are extremely small, which goes unchanged for most of their lives, but as they age, they will actually lose some of the zooxanthellae. James Fatherree talks about this in his book.

It's not just about zooxanthelle (which is brown) when it comes to clam coloration, a main trait which we are looking for is the presence and arrangements of iridocytes.

These iridocytes help mitigate the impact of UV, and even change the wavelength so that it can be available for photosynthesis.


So. I don't think can write it off and say that clam color can't change.
 

minus9

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It's not just about zooxanthelle (which is brown) when it comes to clam coloration, a main trait which we are looking for is the presence and arrangements of iridocytes.

These iridocytes help mitigate the impact of UV, and even change the wavelength so that it can be available for photosynthesis.


So. I don't think can write it off and say that clam color can't change.
There’s also amino acids within the mantle tissue, combined with everything, the mantle can change in appearance depending on light angle, spectrum, etc.
It’s also completely random as well. They’ve conducted several studies where they fed clams zooxanthellae from other colorful clams to see if they would take on those colors and found that no change took place. They even conducted a study with different lighting sources, not all clams in the study changed color or appearance, but some did. So it’s possible that clams have the ability to change or at least create camouflage to reflect or absorb uv and other spectrums of light. But from what I’ve seen keeping clams and the books that I’ve read, it’s completely random and not all clams will change color. At least not in the same way that corals do. I watched my purple/gold maxima change, but it really was a subtle change. It seemed to darken up a little and get deeper colors, but also lost some contrast between the colors. Whereas before, there were distinct lines between the colors/pattern. So it’s completely possible that there can be color changes in the mantle, but it seems to be random at best. They are simply amazing animals and truly unique.
 

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There’s also amino acids within the mantle tissue, combined with everything, the mantle can change in appearance depending on light angle, spectrum, etc.
It’s also completely random as well. They’ve conducted several studies where they fed clams zooxanthellae from other colorful clams to see if they would take on those colors and found that no change took place. They even conducted a study with different lighting sources, not all clams in the study changed color or appearance, but some did. So it’s possible that clams have the ability to change or at least create camouflage to reflect or absorb uv and other spectrums of light. But from what I’ve seen keeping clams and the books that I’ve read, it’s completely random and not all clams will change color. At least not in the same way that corals do. I watched my purple/gold maxima change, but it really was a subtle change. It seemed to darken up a little and get deeper colors, but also lost some contrast between the colors. Whereas before, there were distinct lines between the colors/pattern. So it’s completely possible that there can be color changes in the mantle, but it seems to be random at best. They are simply amazing animals and truly unique.
I think I have read the article you mentioned here. I agree totally with you, tridacna are such amazing animals.

I'm really hoping as a community we can really have better understanding about tridacna physiology. Then perhaps we will have more targeted approach to show them in the best light (pun intended).
 
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I think I have read the article you mentioned here. I agree totally with you, tridacna are such amazing animals.

I'm really hoping as a community we can really have better understanding about tridacna physiology. Then perhaps we will have more targeted approach to show them in the best light (pun intended).
They look best under full spectrum day light. I’m setting up a shallow nano and thinking of using a Kessil Tuna sun instead of the tuna blue. 6500k does wonders with clams. My main tank I’m switching back to 14k halides and will have several species of clams.
 

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They look best under full spectrum day light. I’m setting up a shallow nano and thinking of using a Kessil Tuna sun instead of the tuna blue. 6500k does wonders with clams. My main tank I’m switching back to 14k halides and will have several species of clams.
A neutral light makes clam look good, certainly. But it probably offers less PUR compared to a bluer spectrum. So it's a balance imo.
 

oreo5457

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They look best under full spectrum day light. I’m setting up a shallow nano and thinking of using a Kessil Tuna sun instead of the tuna blue. 6500k does wonders with clams. My main tank I’m switching back to 14k halides and will have several species of clams.
Hmmm...Kessils fw tunas lights generally lack color quality though it " might" depend on the generation.
Anyways with a " color" temp range of 6000- 9000-ish they will be low on warm wavelengths.
And a poor cyan output.
Since you like warmer(10-14000k) halides you may not be happy w/ the color rendition of the Kessils.

It is hard to be exact since kessil doesn' t release pertinent info.
I also have s suspicion that they changed their diode composition without any notice .

See graphs in post #2

360X is a completely different animal though.
 
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minus9

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Hmmm...Kessils fw tunas lights generally lack color quality though it " might" depend on the generation.
Anyways with a " color" temp range of 6000- 9000-ish they will be low on warm wavelengths.
And a poor cyan output.
Since you like warmer(10-14000k) halides you may not be happy w/ the color rendition of the Kessils.

It is hard to be exact since kessil doesn' t release pertinent info.
I also have s suspicion that they changed their diode composition without any notice .

See graphs in post #2

360X is a completely different animal though.
I will most likely use one of my extra 360x’s on the 10k setting or 100% color at first. But we’ll see?
 

vahegan

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Hi Dana, thanks for an interesting thread. A lot of good reading, I love those scientific articles that leak into the hobby.
I always assumed that Tridachna clams need as much light as possible, because they are mostly photosynthetic but, unlike SPS corals, have much more complex structure, including a heart and other organs to run, hence need to get much more of energy. Plus, my personal observation was that they like a bit of nitrate, say, 5-10ppm. That said, I never had success with small clams, but any larger than 3" were doing well.
 
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J1a

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I have added a squamosa clam to my aquarium one week ago. Within the week, the clam showed marked change in the contrast of the mantle.

PSX_20220114_173405.jpg


So perhaps Par and spectrum could change the look of a tridacna, to a certain extent.
I love clams. So here comes the week 2 update on that squamosa.

IMG_20220121_160440.jpg


The clam started to develop blue spots since last week (The red circled area, among others). The spots are hard to capture on camera, but it's obvious enough to see with my eyes. Hence for the photo the contrast is adjusted.

Another interesting observation is at the area near the edge of the mantle. There are pin sized area with extremely strong iridiance. The bright blue exceeds that of the Tahitian maxima clam. If you peer closely at the zoomed in photo, you should be able to spot it.

Let's see if there will be further development.
 

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