Coral Coloration & Trace Element Experiment

[Randy Holmes-Farley]

For rapidly depleting trace elements, water changes would seem to be a very expensive way to try to maintain them. I’m also not sure it makes much sense to get a salt mix based on its trace elements since in a short period of time it won’t have mattered what was there.

 

[lpramos]

For rapidly depleting trace elements, water changes would seem to be a very expensive way to try to maintain them. I’m also not sure it makes much sense to get a salt mix based on its trace elements since in a short period of time it won’t have mattered what was there.

I buffer my fresh saltwater bucket with rapidly depleting trace elements. I do AWCs throughout the week from the bucket.

Do the rapidly depleting trace elements stay in the fresh saltwater in their original ionic form?

 

[taricha]

For rapidly depleting trace elements, water changes would seem to be a very expensive way to try to maintain them. I’m also not sure it makes much sense to get a salt mix based on its trace elements since in a short period of time it won’t have mattered what was there.

On the one hand I agree, and so does the chemical data from my system - water changes are not trace element dosing - except for a very small handful of elements, the trace input is essentially nothing. In my case more elements were diluted lower by water changes than added.
However there seem to be a few elements where even a typical 10% weekly water change actually brings in enough to matter to some organisms. I already talked a good bit about the boost in photosynthetic growth that I (and others) observe, but this reminded me of another from my notes that accidentally escaped my write-up.

My chem measurements show iodine consistently about as low as possible, (.005-.007ppm) and my instant ocean to have abundant iodine (~0.1ppm). By 4 weeks into the water-changes Phase, my gorgonian showed multiple new growth offshoots that it had not in the months prior. (orange circles below)

I'm aware that it's not totally known if the iodine use by gorgonians may simply be incorporation into the support structure, and perhaps isn't an absolute need for growth. I just consider this one data point that maybe water changes with an iodine-replete salt in an otherwise I-starved system could encourage new gorgonian growth.

 

[Randy Holmes-Farley]

I buffer my fresh saltwater bucket with rapidly depleting trace elements. I do AWCs throughout the week from the bucket.

Do the rapidly depleting trace elements stay in the fresh saltwater in their original ionic form?

Depends on what you add and how long you wait. Many will change on addition to the tank, and some, such as unchelated ferrous iron, may air oxidize and become less soluble.

 

[bubbgee]

A couple of updates on how the experiment will progress.
I wasn't sure what I'd do for phase 4




I've opted for a more detailed element management for phase 4. This will follow phase 3 where the Red sea trace mix is added, to see if managing more traces individually has any detectable advantages.
I'll cross reference Randy's list of possibly worthwhile elements with what ICP-MS says about my water and what Moonshiners says target levels / input rates should be for the ppb level trace elements. I'll use the captiv8 single element minor and trace pack. The missing ones I'll use other sources.
This will be the list of elements managed...

After that, I'll have a phase 5: "do nothing - again" where I go back to maintaining the tank with minimal trace inputs, and see if whatever benefits were seemingly observed during the interventions would be observed to decrease.

Why not try something like All For Reef for a month and collect data? Everyone seems to use it and I am not convinced it worked for me while I did. I switched back to three-part after that episode. If anything, I got dinos when I used it (probably unrelated but the carbon dosing component on it help bottom out my nutrients).

 

[bubbgee]

I found this similar study..

 

[taricha]

I found this similar study..

thanks! I'll check it out.

 

[taricha]

The takeaway from this round of element data is that water changes don't actually change very much - numerically. They may be an important source of limited traces, but in my case measurements say only a very few elements are actually being added in notable amounts from the water changes, compared to my water:
Sr, F, I, Mn.

to support this point I sent a separate ICP-OES (FM) of my new mixed I.O. Wanted to make sure that analysis based on ICPs done by others for what I expected to be coming in from my I.O. was reasonable.

the results are as expected. Comparison of my I.O. vs my tank water.
Sr - 10.9 ppm, tank water 5-6ppm
Iodine - 220 ppb (actually more like ~100ppb, FM overshoots this) , tank water below 8ppb
Mn - 33.9 ppb, tank water below 0.2ppb
(F - not measured)

all other elements are similar levels to tank water measurements or lower, so water changes with I.O. are pretty clearly adding significant amounts (compared to the stable low levels in tank water over months) of a few elements, but really only these four.
Somewhat strengthens the case for increased photosynthetic growth with water changes (dustings of microalgae on glass etc) to Mn in my particular situation.

 

[Julie'sreef]

Cool. I'm subscribing to this.. Any videos in the future or just pics?

I'm new here. How can I subscribe to this ?

 

[bubbgee]

I'm new here. How can I subscribe to this ?

At the top of the post, you can click on Watch. There are only pics so far and no videos.

 

[taricha]

I found this similar study..

thanks! I'll check it out.

So the video is nice - for those wondering what's in it, it's like 80% a discussion of these articles below.

The Dana Riddle articles also include references to the papers he pulled that info from.
another reading tip.
check out stuff authored/co-authored by Jorg Weidenmann on google scholar.

This one is fantastic:
Blue light regulation of host pigment in reef-building corals
(the pictures/charts on page 5 are worth way more than 1000 words. )

another
Diversity and Evolution of Coral Fluorescent Proteins

and two more
Contributions of host and symbiont pigments to the coloration of reef corals

It’s cheap to be colorful Anthozoans show a slow turnover of GFP-like proteins

 

[taricha]

Updates on this.
Here's how I should have measured coral fluorescence - and how I would recommend any interested in trying to quantify coral color comparisons to do it. I would have if I had read this paper a little more carefully earlier.
Blue light regulation of host pigment in reef-building corals, D'Angelo et al.
See pg 5 - here's a tiny snippet.

Use fixed color LED lighting in the same position, put a good filter over the camera and shoot the photos on all manual identical settings. Use Blue LEDs to drive green fluorescence, and green LEDs to look for red/orange fluorescent pigments. compare identical camera setting pictures over time.

Advantages over my pigment extraction: Faster, easier, non-destructive, less equipment, can visualize the entire colony, fine for corals that would be hard to sample, more obviously relevant to appearance than a pigment extraction....

a couple of example shots from my tank 3 weeks apart (showing no obvious differences - just an illustration of method)

You can see that corals without fluorescent pigments (gorgonians in the foreground) show up nearly totally dark....

I'll be adding this method to what I'm already doing going forward.

 

[Dan_P]

Updates on this.
Here's how I should have measured coral fluorescence - and how I would recommend any interested in trying to quantify coral color comparisons to do it. I would have if I had read this paper a little more carefully earlier.
Blue light regulation of host pigment in reef-building corals, D'Angelo et al.
See pg 5 - here's a tiny snippet.

Use fixed color LED lighting in the same position, put a good filter over the camera and shoot the photos on all manual identical settings. Use Blue LEDs to drive green fluorescence, and green LEDs to look for red/orange fluorescent pigments. compare identical camera setting pictures over time.

Advantages over my pigment extraction: Faster, easier, non-destructive, less equipment, can visualize the entire colony, fine for corals that would be hard to sample, more obviously relevant to appearance than a pigment extraction....

a couple of example shots from my tank 3 weeks apart (showing no obvious differences - just an illustration of method)

You can see that corals without fluorescent pigments (gorgonians in the foreground) show up nearly totally dark....

I'll be adding this method to what I'm already doing going forward.

Almost completely irrelevant to your situation but the saying came to mind when I read your post, ”a day in the library can be worth a week in the lab”.

Hey, do I detect growth in your corals? That is pretty cool and quantifiable, maybe with image subtraction.

 

[taricha]

Almost completely irrelevant to your situation but the saying came to mind when I read your post, ”a day in the library can be worth a week in the lab”.

Hey, do I detect growth in your corals? That is pretty cool and quantifiable, maybe with image subtraction.

just as observation, the growth rate has seemed to ramp up in the later phases of the experiment.
But add that as another disadvantage of my chosen pigment measurement method. It really complicates growth rate analysis when you are chopping hunks off the corals. Nonetheless, there likely is some analysis possible.

 

[taricha]

Chemical and Coral color data from after Phase 3: Red Sea Trace A & C dosing (6 weeks of Trace element Dosing)

The amount of dosing was done by testing the "headliner" elements in each bottle as Red Sea recommends. Trace A (Iodine, Br, F) was dosed to try to move toward 0.060ppm Iodine. This involved spikes to 0.060 and an eventual daily rate of 22ppb/day of iodine, and then 75% of that the last 2 weeks = 16.5ppb/day Iodine. Trace C (Iron, Cr, Mn, Co, Ni, Cu, Zn) dose was ramped up in the first 2 weeks to a couple of spikes to the Red Sea target of 150ppb Fe, then was dosed at a daily rate that allowed a constant measurable Fe concentration well above the uncertainty of my Hanna chemical test. This was 8ppb/day Fe for 2 weeks then cut back to 4ppb/day Fe the last 2 weeks.
Here's what the Iodine and Fe concentration trends looked like during dosing.

Day 0-4: Spike followed by tracking depletion rateDay 6: 2 day dose
other spikes shown are daily dosing of 22ppb Iodine/day.
after day 16, the dose was cut back to 16.5ppb/day for the next 2 weeks.

Day 0-4: Spike followed by tracking depletion rate
Day 6: 2 day dose
other spikes shown are daily dosing of 8ppb/day Fe.
on day 16 I decided that persistent levels of 20 ppb was higher than needed for any purpose - biological or measurement, and so the dose was cut in half to 4ppb/day Fe for the next 2 weeks.
In accordance with Oceamo testing instructions to not test water within 48hr of Trace dosing or big water changes, I took samples for testing 3 days after the last Trace dosing.

And here is the measurement data.
Phase 3 Chemical Data -

page 2

Within the "PPM elements" nothing changed significantly except for Iodine that was specifically dosed. F and Br which are also in Red Sea Part A were unchanged.

On the "ppb elements"....
Almost all of the elements listed in Red Sea Trace C (highlighted in Teal) increased measurably in concentration - only Mn which seems really difficult to add enough to keep measurable, and Cu which there was already plenty of did not increase in concentration. Al, Ni, Fe, Zn, Cr, and Co were all raised by dosing but not by any previous intervention.

Overall, Red Sea Trace C was surprisingly effective at raising trace elements - I had expected that maybe only a couple would be moved by dosing, but almost all the listed elements increased measurably, and ICP did a fairly good job of measuring those changes. The fact that the dosed elements increased only during the dosed phase and not earlier interventions along with the fact that no "non-dosed" elements showed increases makes me more confident in the results, Especially from Oceamo ICP-MS moreso than FM ICP-OES which was less consistent in these ranges.

 

[Randy Holmes-Farley]

One obvious reason to also like the photo way of tracking fluorescence is that it shows that the changes are least potentially visible by eye, where extraction doesn't necessarily prove that since it may happen in places that would not be readily visible (such as deep enough in tissue where the exciting light doesn't penetrate well or the emitted light doesn't escape well, or both).

 

[taricha]

One obvious reason to also like the photo way of tracking fluorescence is that it shows that the changes are least least potentially visible by eye, where extraction doesn't necessarily prove that since it may happen in places that would not be readily visible (such as deep enough in tissue where the exciting light doesn't penetrate well or the emitted light doesn't escape well, or both).

Yep! Much clearer that what's being measured is what we are interested in.

 

[taricha]

So here is the coral color data from Phase 3 - Red Sea Trace Part A & C
The sinularia shows no color improvements to the eyeball or to the camera over phases 0,1,2, and 3.

The sarcophyton seems photographically to have possibly increased in green brightness during phase 3

Next are the orange monti cap and green pocillopora, these also seemed to show noticeable differences to the eye, camera or both.

The photographs might indicate more intense orange, and to the eyeball the orange seems more intense as well. (we could also make an observation here about the relative growth rate during phase 3 vs previous.)


and here's the pocillopora....

While I didn't notice any color increase by eyeball in normal conditions like this, the photograph looks like more intense green is possible. (again, we could note growth rate differences).
A comment and apology for the light fields in phases 2 and 3 looking different than 0 and 1. I chose at the beginning of the experiment to photograph in "full light" which means all my lights on and the window blinds open as I always have them. The window blinds open introduced more or less ambient sunlight during some photo sessions than others. That uncontrolled variable was a poor choice.
Fortunately we have some unambiguous observations...
Photos with the polyps retracted reveal the amount of green in the pocillopora skin...

I did not photograph this aspect of color routinely, because it simply wasn't present early in the experiment so I didn't know to monitor it - it was a dramatic increase that became very apparent during phase 3, but if you inspect the phase 0 picture closely, you'll see the slightest blush of green skin present there as well - just far far less.


Here's the monti digitata - very noticeable eyeball change in the increase in green coloration both on polyps (a green sheen) and skin on several spots indicated by arrows...

Here's another shot with polyps retracted in normal light to better illustrate...

While the green skin at the locations of new growth might make us wonder if growth rate is really the controlling variable, in the earlier phases there were lots of regions of new growth that had no green skin whatsoever.

here's blue LED+yellow filter images to track the spread of the green skin pigment...

And here's a bonus coral. During phase 0, I acquired a green monti cap frag.
It lost coloration in my system over a month in my system and became almost entirely brown. Then during phase 3 it regained green coloration. The frag is small and far from the glass and difficult to photograph but the color changes are still observable.

(first 3 pictures are not always under the same photo/lighting settings, but the last 3 pictures are)

Phase 2 pigment extraction data
(this will be shared later, but it's not as clear as the photographs, bummer.)


Commentary on Phase 3:
The Red Sea Trace A (Iodine, F, Br) added easily trackable Iodine - no increase in F or Br was measured, and Part C (Iron, Cr, Mn, Co, Ni, Cu, Zn, and Al) added easily measurable Fe, Cr, Co, Ni, Zn, and perhaps Al - no increase in Mn, Cu. The increase in green fluorescence and orange in the monti cap was clearly observed across multiple corals. Anecdotally, 4 weeks into the 6 week trace dosing, two people who are not hobbyists but pass by the tank regularly - unprompted - told me that the tank looked "brighter" and asked me if I changed the lights (there were no light changes). During this time, nutrients and major parameters were held essentially constant. This along with the fact that the obvious color increases were not observed during the earlier interventions (algae/phyto input and heavy water changes) adds more confidence that the trace supplementation was the driver. I have guesses but I do not have good theories on which elements were the drivers of these color changes. My overall impression of the appearance of the tank and coral color after phase 3 is that if the corals had looked like this at the beginning, I would not have conducted this experiment. The colors are visually bright and there are no corals that lack the basic primary colors they should have.

Caveats:
1. Some of the colors that were lacking are the absolute most basic ones (green in green monti cap and the monti digi). This indicates that my tank conditions were possibly well out of the normal hobby range for such common corals to lose their most basic colors. In that sense, my results may not be applicable to very many systems.

2. Now (in the future) 6+ weeks after stopping trace dosing at the end of Phase 3, the coral color continued to increase and has shown no signs of reverting. I previously staked out my position that I need to see colors fade after trace dosing was ended in order to be very confident in the effect. So that piece of evidence is a long time coming and still waiting. So for the moment, although I am persuaded that the trace dosing was effective I am currently in the camp "I stopped Trace dosing and nothing changed." We'll see how long that remains the case.

 

[Dan_P]

So here is the coral color data from Phase 3 - Red Sea Trace Part A & C
The sinularia shows no color improvements to the eyeball or to the camera over phases 0,1,2, and 3.

The sarcophyton seems photographically to have possibly increased in green brightness during phase 3

Next are the orange monti cap and green pocillopora, these also seemed to show noticeable differences to the eye, camera or both.

The photographs might indicate more intense orange, and to the eyeball the orange seems more intense as well. (we could also make an observation here about the relative growth rate during phase 3 vs previous.)


and here's the pocillopora....

While I didn't notice any color increase by eyeball in normal conditions like this, the photograph looks like more intense green is possible. (again, we could note growth rate differences).
A comment and apology for the light fields in phases 2 and 3 looking different than 0 and 1. I chose at the beginning of the experiment to photograph in "full light" which means all my lights on and the window blinds open as I always have them. The window blinds open introduced more or less ambient sunlight during some photo sessions than others. That uncontrolled variable was a poor choice.
Fortunately we have some unambiguous observations...
Photos with the polyps retracted reveal the amount of green in the pocillopora skin...

I did not photograph this aspect of color routinely, because it simply wasn't present early in the experiment so I didn't know to monitor it - it was a dramatic increase that became very apparent during phase 3, but if you inspect the phase 0 picture closely, you'll see the slightest blush of green skin present there as well - just far far less.


Here's the monti digitata - very noticeable eyeball change in the increase in green coloration both on polyps (a green sheen) and skin on several spots indicated by arrows...

Here's another shot with polyps retracted in normal light to better illustrate...

While the green skin at the locations of new growth might make us wonder if growth rate is really the controlling variable, in the earlier phases there were lots of regions of new growth that had no green skin whatsoever.

here's blue LED+yellow filter images to track the spread of the green skin pigment...

And here's a bonus coral. During phase 0, I acquired a green monti cap frag.
It lost coloration in my system over a month in my system and became almost entirely brown. Then during phase 3 it regained green coloration. The frag is small and far from the glass and difficult to photograph but the color changes are still observable.

(first 3 pictures are not always under the same photo/lighting settings, but the last 3 pictures are)

Phase 2 pigment extraction data
(this will be shared later, but it's not as clear as the photographs, bummer.)


Commentary on Phase 3:
The Red Sea Trace A (Iodine, F, Br) added easily trackable Iodine - no increase in F or Br was measured, and Part C (Iron, Cr, Mn, Co, Ni, Cu, Zn, and Al) added easily measurable Fe, Cr, Co, Ni, Zn, and perhaps Al - no increase in Mn, Cu. The increase in green fluorescence and orange in the monti cap was clearly observed across multiple corals. Anecdotally, 4 weeks into the 6 week trace dosing, two people who are not hobbyists but pass by the tank regularly - unprompted - told me that the tank looked "brighter" and asked me if I changed the lights (there were no light changes). During this time, nutrients and major parameters were held essentially constant. This along with the fact that the obvious color increases were not observed during the earlier interventions (algae/phyto input and heavy water changes) adds more confidence that the trace supplementation was the driver. I have guesses but I do not have good theories on which elements were the drivers of these color changes. My overall impression of the appearance of the tank and coral color after phase 3 is that if the corals had looked like this at the beginning, I would not have conducted this experiment. The colors are visually bright and there are no corals that lack the basic primary colors they should have.

Caveats:
1. Some of the colors that were lacking are the absolute most basic ones (green in green monti cap and the monti digi). This indicates that my tank conditions were possibly well out of the normal hobby range for such common corals to lose their most basic colors. In that sense, my results may not be applicable to very many systems.

2. Now (in the future) 6+ weeks after stopping trace dosing at the end of Phase 3, the coral color continued to increase and has shown no signs of reverting. I previously staked out my position that I need to see colors fade after trace dosing was ended in order to be very confident in the effect. So that piece of evidence is a long time coming and still waiting. So for the moment, although I am persuaded that the trace dosing was effective I am currently in the camp "I stopped Trace dosing and nothing changed." We'll see how long that remains the case.

As you near the end of this study, are you thinking there should be a “2.0” version of the study utilizing what you learned in this study? Or are you ready to move on? I was thinking a study of 16 nubbins in separate containers from the same species would remove variability seen in an aquarium study.

 

[Randy Holmes-Farley]

Thanks for the study, taricha!

As a separate question for folks following fluorescence of corals, is there much evidence of fluorophores in corals that need excitation below 400 nm to give visible fluorescence?

Reason for asking is thinking about possible lights for my tank, and the lowest led available is listed as:

AI blade has 405 nm plus a 415 nm
GHL LB3 has one called 385/405 nm and 425 nm
Straton Pro has 405 and 420 nm

The issue is whether the 380 nm on the GHL is useful/important