Crocea's loose color???

[EnderG60]

OK so was talking with my boss and he mentioned that crocea's tend to loose color as they age/grow. When I got home I noticed that mine had indeed lost some of its intesity over the past year when comparing it some pics from a while ago. While still happy and healthy its just not as colorful.

I also have a client that was wondering why his 3 year old crocea had pretty much lost all its color...

So Im wondering what causes this?

 

[reefman23]

What sort of lighting, parameters, tank sizes, etc?

Jesse

 

[EnderG60]

originally in a 15g nano with a 150w pheonix 14k for a year, and near perfect water peramiters. Now in a 58g with a 400w xm20k and specs as follow

Ph - 8.1
Trites/ammonia - 0
Nitrates - 15-20
Alk - 3-4 mg/l
Calc - 350-450
Phosphate - .01
Temp - 80

as I said it has always seemed happy and opens really nice, and has been growing pretty well since I got it.

Pick in the nano

Crappy current pic

It still looks ALOT better then that last pic, but its no where near what it was 2 years ago.

 

[mbbuna]

150w pheonix 14k

<a href=showthread.php?s=&postid=8890458#post8890458 target=_blank>Originally posted</a> by EnderG60
Now in a 58g with a 400w xm20k

forget about the watts. you are going bluer from 14 to 20k and moving the clam down in the tank more. Croceas dont receive 14k or 20k light in the wild. most of the vibrant color you see in them comes from the clam putting out protective pigments to shield itself from very bright, full spectrum light

 

[EnderG60]

It has also lost color when viewing from the top down and in pictures with a flash. And realisticly the color of the 150w 14k phoenix is actually bluer then a 400w 20k xm...it just is.

Are you saying its loosing color because it doenst need as much protection or the lighting is not "reflecting" as much color?

 

[mbbuna]

here is a comparison of an AC14k 150w(phoenix wasn't tested so this is the closest one) and a 20k XM 400w. to your eye the 14k may look bluer but the plot clearly shows the 20k is alot bluer.

Are you saying its loosing color because it doenst need as much protection or the lighting is not "reflecting" as much color?

a little bit of both, the bright protective pigments the clam produces reflect away and/or convert less usable light. so when you use a bulb that focus' on one small slice of the spectrum the clam will slowly drop some of its pigments and the zoox that prefers that spectrum will start to dominate. so what you get in time is a less vibrant clam that you can see right to its zoox (brown)

 

[jmaneyapanda]

I have to say, I agree with some and disagree with some. Mbbuna is absolutely right that the 20K is bluer than the 14K. It may not appear so, but that is the way it is. But, I disgaree that you can disregard the wattage. A 400 watt 20K should still make more than adequate light for this clam. I do think a lower K would be better, though. If you think the only factor which caused this color shift would be light (I doubt age has anything to do with it), then lower the K rating on your bulb. Bear in mind, if you are indeed belaching, it could be many many other parameters (ie- temp, salinity, etc.)

 

[mbbuna]

<a href=showthread.php?s=&postid=8894803#post8894803 target=_blank>Originally posted</a> by jmaneyapanda
But, I disgaree that you can disregard the wattage.

i meant that more so we could just think about the spectrum for now. higher wattage bulbs will definitely give more light, but when you move to these more focused spectrum bulbs (like 20k)whatever species of zoox that can use that spectrum best will dominate. in some corals this can be very pleasing, but some times in clams you will get less the pleasing results.

if you provide shallow water high light clams(that really is all we keep) with intense full spectrum light ,you keep all of the different species of zoox it keeps happy. so then the clam needs to keep less zoox(total)and can shield(reflect) less or unusable light and floress(if thats a word ) some light to a more usable spectrum. that where the vibrant colors and "electric" glow come from.

 

[jmaneyapanda]

Yes, I would agree with that. I guess misunderstood what you meant by disregarding. But, what spectrum is given by the 14K that is not by the 20K? When I look at the spectral plots, I see that if anything, the 20K has a little bump post 660 nm, where the 14 K doesn't. There is no wavelength where the 14K is providing what the 20k isn't also.
Now, I'm not trying to compare apples and oranges, though. I know a 14K and 20K of thw same wattage are not comparable. I showed myself this by switching from 20K back to 10K in my tank recently.

 

[mbbuna]

what 14k and 20k will put out is going to change from mfg. to mfg. and ballast ect. and as you know genetic differences from clam to clam come into play also.

here you can see a higher spike in blue in the 20k but the 10k is much fuller, giving "overall" more blue, plus more green, yellow and red

 

[mbbuna]

 

[mbbuna]

im trying to get a good apples to apples on 14k to 20k from the same mfg. ballast ect and i found one but now imageshack isnt being my friend.

your right there isnt much difference

 

[jmaneyapanda]

Yes, but in the first spectral plot, there is no diffrentiation as you showed. That is my only point. I COMPLETELY understand that the various K ratings will produce different representations at different wavelengths. I simply meant to show that, as per the first spectral plot you showed, the 400 watt 20K does provide better light than the 150 watt 14K- at all wavelengths.

 

[mbbuna]

 

[mbbuna]

there's 1/3 more ppfd in the 14k, and it looks like its all in the green, green blue and violet

 

[mbbuna]

<a href=showthread.php?s=&postid=8896305#post8896305 target=_blank>Originally posted</a> by jmaneyapanda
I simply meant to show that, as per the first spectral plot you showed, the 400 watt 20K does provide better light than the 150 watt 14K- at all wavelengths.

yes but with that huge blue spike its going to cause one species of zoox to dominate.

im not saying it will be critical to the health of the clam, but it may lose some of it color

 

[jmaneyapanda]

I'm not making my point clear. Look at the first spectral plot you posted. This is the plot I am referring to. To be honest, I am surprised there is not more variable in wavelengths produced, but it shows no diffentiation in the wavelengths.

I am of the same opinion as you, but in the case shown in THAT PARTICULAR PLOT, the 400 watt 20K is a better bulb.

 

[jmaneyapanda]

From your last post, I see the point you are trying to make. I dont necessarily agree with it, but I understand.

 

[EnderG60]

ok so spectral plots aside, why would a crocea loose color while a maxima would not?

and if I were to put the clam back under a 10k bulb would it regain some of its color?

 

[mbbuna]

<a href=showthread.php?s=&postid=8898716#post8898716 target=_blank>Originally posted</a> by EnderG60
ok so spectral plots aside, why would a crocea loose color while a maxima would not?

different clams, different genetics, different locations ect...

and if I were to put the clam back under a 10k bulb would it regain some of its color?

if the spectrum is the cause then yes, but it wont happen over night, it may take a few months.