Coral color, trace & lighting experiment pt2

[Doctorgori]

Oddly enough Ive been thinking about this for a VERY long time. spurred or inspired by the plethora of claims by both industry suppliers and hobbyist alike on claims that a particular product or methodology will yield a improvement in coral colors…

This is sort of a big deal, or at least it has spawned a TON of products and related/derivative youtube vids on the topic.

I have actually been working on this for a few months now but the sheer cost of just setting this up plus the time it takes to get supplies in has been delaying this project/experiment for weeks …

So today as part of some background research Ive been sifting through Youtube vids and along with cursory search here I stumbled upon this thread:

Coral Coloration & Trace Element Experiment by @taricha

So while my individual expertise in this area is more Dunning - Krueger, @taricha has demonstrated a more educated/scientific approach in many of his/her threads (I dont know your gender, pardon)

I would love to reference the above thread to avoid duplication and /or perhaps compliment the other thread in tandem as apposed to in lieu of…

My approach is different however:

I am using 2 test tanks (one lit @6500K and another lit at 28000K) with 2 sets of near identical sets of corals purchased at the same time and at approximately the same size …the difference and twist being to ALSO measure/photograph/document growth/coloration in two different color temps in the same saltwater “bath” so to speak …

The above “pairs” were cop’d from WWC and are marinating in my DT to weed out losers prior to another dip and then placement

Shown below is the whole setup pre-fill

And the spaghetti of dosers, tubes et et

A TON of open questions and derivative questions here as well as experiments
Mainly I wish to find out if there is any influence on lighting when corals coloration are raised under dissimilar color temps, also is the corals ability to achieve certain colors when raised under different lighting environments affected or does it even matter?
Added: I will be pulling the “twin” corals from time to time and comparatively photographing them out of water under daylight

Also what exactly does work “chemically” to obtain different colors and intensity? (Probiotics, Trace colors, et et)
..what part does flow and temperature play…

Another important design feature is the purposeful absence of a dedicated biofilter. While fully realizing bacteria will occupy all surfaces anyway. I’ve designed the system to alleviate as much “bacterial noise” as much as possible

Also absent will be any CUC so my CA & trace element intake can be measured somewhat more accurately..emphasis on “somewhat”…

I will be adding fish to both feed phyto indirectly to the corals and “attempt” to keep pest algae under control. These will be converted freshwater Limias. Freshwater sourced to mitigate pest, contaminants and any other potential “biotransfers” (for lack of a more educated term) …
In fact they JUST arrived

A side “bet” is algae management under “white light” vs blue. Since the MH crowd has no “white channel” to turn off. Input from that side would be greatly appreciated

For now any food energy will be plankton based either directly or indirectly via a assortment of pods

I am currently going through a MAJOR setback as all of my phyto cultures are crashing (gotta tighten up on the sterilization protocols) arrghh

 

[MnFish1]

Oddly enough Ive been thinking about this for a VERY long time. spurred or inspired by the plethora of claims by both industry suppliers and hobbyist alike on claims that a particular product or methodology will yield a improvement in coral colors…

This is sort of a big deal, or at least it has spawned a TON of products and related/derivative youtube vids on the topic.

I have actually been working on this for a few months now but the sheer cost of just setting this up plus the time it takes to get supplies in has been delaying this project/experiment for weeks …

So today as part of some background research Ive been sifting through Youtube vids and along with cursory search here I stumbled upon this thread:

Coral Coloration & Trace Element Experiment by @taricha

So while my individual expertise in this area is more Dunning - Krueger, @taricha has demonstrated a more educated/scientific approach in many of his/her threads (I dont know your gender, pardon)

I would love to reference the above thread to avoid duplication and /or perhaps compliment the other thread in tandem as apposed to in lieu of…

My approach is different however:

I am using 2 test tanks (one lit @6500K and another lit at 28000K) with 2 sets of near identical sets of corals purchased at the same time and at approximately the same size …the difference and twist being to ALSO measure/photograph/document growth/coloration in two different color temps in the same saltwater “bath” so to speak …

The above “pairs” were cop’d from WWC and are marinating in my DT to weed out losers prior to another dip and then placement

Shown below is the whole setup pre-fill

And the spaghetti of dosers, tubes et et

A TON of open questions and derivative questions here as well as experiments
MainlyI wish to find out if there is any influence on lighting and a coralsbase coloration or ability to achieve cerain colors when raised under different lighting enviorments

Also what exactly does work “chemically” to obtain different colors and intensity..
..what part does flow and temperature play…

Another important design feature is the purposeful absence of a dedicated biofilter. While fully realizing bacteria will occupy all surfaces anyway. I’ve designed the system to alleviate as much “bacterial noise” as much as possible

Also absent will be any CUC so my CA & trace element intake can be measured somewhat more accurately..emphasis on “somewhat”…

I will be adding fish to both feed phyto the corals and “attempt” to keep pest algae under control. These will be converted freahwater Limias. Freshwater sourced to mitigate “biotransfers” (for lack of a more educated term) …
In fact th yJUST arrived

A side “bet” is algae management under “white light” vs blue. Since the MH crowd has no “white channel” to turn off. Input from that side would be greatly appreciated

For now any food energy will be plankton based either directly or indirectly via a assortment of pods

Very nice description and set up. One thing I would consider is listing your theses ahead of time - as compared to adding things on during the experiment. One thing I will mention - how will you measure success (i.e. whether one light is better or worse vis a vis coloration) unless you decide to do the measurements under a different light that you're growing the corals under (of course you an also take photos/compare, etc under the light you're using). Best wishes with your experiment

 

[Doctorgori]

Forgot to add more design elements

Very nice description and set up. One thing I would consider is listing your theses ahead of time - as compared to adding things on during the experiment. One thing I will mention - how will you measure success (i.e. whether one light is better or worse vis a vis coloration) unless you decide to do the measurements under a different light that you're growing the corals under (of course you an also take photos/compare, etc under the light you're using). Best wishes with your experiment

Thats a great question.

Since this is a growth and coloration experiment, most documentation will be via daily photographs next to rulers or whatever . I actually have a webcam on the way and if it works out I will mount 1ea above each tank.

I am waiting (but not holding my breath) for any sales on Neptune gear as I want to shell out for a Trident and also the somewhat flaky NP unit. For logging, The Apex head unit is in depot and no telling when that gets here…

Built in the design are failure “bailouts”: 600gal in buckets of IO purple with a Neptune DOS for AWC @ 2% daily (from a adjacent 32g rubbermaid prefilled) …if things get funky we can up that to any percentage we want, again I got stockpiles of salt…

I also have.a 55w UV unit in line for the inevitable and expected bacterial blooms since there is no biofilter …

There is also a 5 g macro reactor powered by 2 Tunze LED’s …undecided if I power that with chaeto or ulva…(Someone sent me some garbage, dying and stinky ULVA btw) …so looks like I will have to live with messy return pump tangling chaeto unfortunately?…

Also if needed there is a Red Sea Skimmer with a variable output and a Red Sea DCreturn pump…

 

[Doctorgori]

Also forgot dosing…I’m just going to go with Tropic Marins line initially…Less “hocus pocus” and magical claims, plus Balling is pretty solid and proven…

Not sure how All For Reef would work in a bacterially deficient setup…so I decided on traditional 2/3 part for CA & Alk …also controlled dosing is possibly in play

I will assume Aminos are required but I will dose whatever anyone following the thread suggest…

I will have their “Elini Phos Rapid” chambered for the inevitable rise in phosphates from phyto dosing…
NO CLUE how to address the nitrogen family of problems, as Ive purposely left out a biofilter or any means to manage the cycle beyond a macro reactor..

Ill defer and need to the crowd for that

 

[MnFish1]

Awesome - my comment about lighting is that to really compare 'coloration' - it has to be compared under the same light. I.e. of course take pictures of the tank under the light they are growing in - but if possible, also add pictures of both tanks under the same light temperature. Great job

 

[bubbgee]

Following this experiment too.

What I would like to see is experiment on actual SPS we want to figure out.. like a WD frag for each setup and see how the lighting and dosing affects the frag.

 

[ajremington68]

sheesh, what does your main display look like that your 'experiment' tank looks this nice and clean? also how did you aquire the alumnium T slotting? Did you have it pre cut, or by the bars and cut on your own. Easy or difficult for either route?
Love the look of it and want to do a frag system with it n the future.

 

[Doctorgori]

Awesome - my comment about lighting is that to really compare 'coloration' - it has to be compared under the same light. I.e. of course take pictures of the tank under the light they are growing in - but if possible, also add pictures of both tanks under the same light temperature. Great job

Yeah and here is some derivatives of that:
The whole 6500k thing to me is unanswered and unsettled…
We have seen/read the over used, widley mentioned chlorophyll A study which supposedly proved once and for all that corals only need be lit by what Ive deemed the “Holy Spectrum” as shown by the grossly ubiquitous chart below (whom by now hasn't seen this)

But besides our own eyeballs numerous post and threads have hinted at something slightly deviating from this chart…
Perhaps many lighting units (Like the Iwasaki MH 6500) has this spectrum imbedded more or less but then there is the oft quoted “red light inhibits coral growth” thing to contend with…even though again our eyeballs say different…
Here are some receipts from 30yrs back

The tank is BATHED in red spectrum all the down in the that nasty 4800K no less…no algae, no noticeable growth inhibition that I could tell…

I want to see what shakes in a side by side…same water, same temps, same chemicals, same conditions
( with the caveat a 6500K LED is not equivalent to a 6500 wide band MH…but we will see anyway)

 

[Doctorgori]

sheesh, what does your main display look like that your 'experiment' tank looks this nice and clean? also how did you aquire the alumnium T slotting? Did you have it pre cut, or by the bars and cut on your own. Easy or difficult for either route?
Love the look of it and want to do a frag system with it n the future.

Looks clean since This build is empty…held up waiting on two GHL Light bars, its been a month and GHL isn't known for fast shipping..Rep said 3 weeks 4 weeks ago LOL

Zyltec (I think) is where I got the tslot from…it wasnt that pricey…maybe $300 ish for everything…I got a 10pack of 1M 30/30 plus a 6pack of the 74” bars…
Make sure you get a non ferrous blade or whatever it is for aluminum

 

[Doctorgori]

@MnFish1
I chewed on this for a minute

One thing I would consider is listing your theses ahead of time - as compared to adding things on during the experiment.

There will be two tanks so nothing stopping me from swapping lights (blue to white and back) then photographing or pulling them out of water as they arent mounted on rocks…I was thinking about placing them on plexiglass sheets so when the base encrust I can pull them out of the water with less disturbance/stress…
Probably will have to do this daily…

Also I was thinking about splitting this into 3 parts, but not sure if I should do it sequentially or concurrently

1) Test the so called “Trace Colors” type of supplements…but no longer sure as the more competent @taricha is doing something similar. Still it would be interesting to see how much latency there is between application and results, or if there is any merit to it at all.

2) Test the so called “Probiotic” approach to color…Off the cuff this should in theory yield a clearer result in a setup free from any nitrification “engines” (if thats possible)… I dont have all the answers here and will need help. Latency is going to be a issue and I can envision daily photography of the test corals

3) test to see if colors are fixed by environment or if its just a play on optics or is it a variable depending on light spectrum…TBH I dunno, has anyone ever done a similar side by side like this against “natural” or wide spectrum lighting?

I have been skeptical on claims about coloration results, heck what did these product manufacturers use as a “control” and was it against wild stock under natural daylight…

Then there are hobbyist claims and color chasing by stickheads…BRS and WWC have all made coloration vids, so I’m not skeptical of those claims per se, but would just like to see these conduced under lower kelvins outside of typical blueish reef lighting…

One thing I will mention - how will you measure success (i.e. whether one light is better or worse vis a vis coloration) unless you decide to do the measurements under a different light that you're growing the corals under (of course you an also take photos/compare, etc under the light you're using).

The corals will have to be removed from water then photographed…I can also see swapping light fixtures then photographing…I can see this being a daily chore, along with a simple ruler measurement…maybe even placing them on a scale…I will need help or this will just be a Dunning-Krueger exercise…

 

[Doctorgori]

Following this experiment too.

What I would like to see is experiment on actual SPS we want to figure out.. like a WD frag for each setup and see how the lighting and dosing affects the frag.

Sorry forgot to answer this , here's my WWC order, all sps…Ive only got a about three orders from them and every frag looked to be growing/encrusting…or at least I didn't get freshly glued “boogers” on a plug

Green Digitata Montipora Coral
$20.00 2$20.00

Green Hirsuta Montipora Coral
$10.00 2$10.00

Pink Polyp Cap Montipora Coral
$20.00 2$20.00

Rainbow Montipora Coral
$20.00 2$20.00

Tequila Sunrise Montipora Coral
$20.00 2$20.00

Tyree Aequituberculata Cap Montipora Coral
$10.00 2$10.00

Tyree Flower Petal Montipora Coral
$20.00 2$20.00

Tyree Sanddollar Porites Coral
$10.00 2$10.00

WWC Money Shot Montipora Coral
$20.00 2$20.00

WWC Lucky Charms Montipora Coral
$20.00 2$20.00

WWC Rainbow Pocillopora Coral
$20.00 2$20.00

WWC Spearmint Montipora Coral
$10.00 2$10.00

Jason Fox Frankies Hot Pink Rim Montipora Coral
$20.00 2$20.00

Castells Banana Table Cookie Acropora
$20.00 2$20.00

Jason Fox Purple Tide Montipora Coral
$20.00 2$20.00

This is from their “value corals”….only one bleached frag…. Definitely acceptable loss for $10 frags

Again these are marinating in my display tank…Ill dip them in Tropic Marins stuff per instructions…hopefully that will keep any biological flotsam/jetsam out…especially those ubiquitous calcium white spiral things (whatever they are) that get all over equipment

 

[Randy Holmes-Farley Verified Community Expert]

Looking forward to the results!

 

[taricha]

@Doctorgori This is excellent. I love the amount of thought you have put into this. Here's some comments and thoughts. (Apologies ahead of time for the critiques.)
When I try to answer an experimental question, I think of how to make the question as small and simple as possible before doing an experiment. Afterward I usually realize I failed, and the experiment I did actually had too many questions at once and so the answers are too complicated to make sense of. This is especially true in biology stuff.
The coral coloration issue is too big and it's too tempting to ask all the questions at once. Don't. Let's start with the smallest simplest one at hand.

I am using 2 test tanks (one lit @6500K and another lit at 28000K) with 2 sets of near identical sets of corals purchased at the same time and at approximately the same size …the difference and twist being to ALSO measure/photograph/document growth/coloration in two different color temps in the same saltwater “bath” so to speak …

Do the lighting-only difference question first.
The lighting effect on the development of coral coloration is so large that it will dominate any other effects being considered. It shouldn't take too long and It's also one where we can ground our results in comparison with what has already been published. It would be good to read some of what's already been done here.
Gonna tag @oreo54 here - a lighting guru. Oreo, could you share some references where differences in lighting spectrum were used to drive the development of coral pigments? I can think of a couple - but I'm sure you have more in your back pocket.

@Doctorgori, the advantage you have over what has been published on that question is the corals are more interesting and the colors present much more varied. How they color shift under the two spectra will be very useful info to hobbyists.

Also, I know what 6500K is, but I only sorta know what 28000K is supposed to mean - "really blue" - but you probably don't actually have a 28,000 Kelvin ball of plasma as a light source - so it'd be more informative to tell us what those two light sources actually are, and maybe post spectra of them if you have them handy.

I am currently going through a MAJOR setback as all of my phyto cultures are crashing (gotta tighten up on the sterilization protocols) arrghh

Why try to drive all nutrition through phyto? That's not how most hobby systems run. It's hard to do and if you succeeded it would make your results harder to replicate for the hobbyist. Culturing phyto is a beast.
If phyto is a central part of something you are trying to do, then I suggest pre-fixed phyto products like these: https://reedmariculture.com/collections/instant-algae-feeds
These are frozen or refrigerated products that will last a long time, are plenty big for the scale you are using and are sufficient for fish rearing - so you know they can deliver nutrition successfully to intermediate organisms like rotifers and copepods that are then able to support raising fish fry. So definitely sufficient nutrition. If you have to master multi phyto culturing first, you'll be waiting a few months - and it'll be (even more) expensive.

Another important design feature is the purposeful absence of a dedicated biofilter. While fully realizing bacteria will occupy all surfaces anyway. I’ve designed the system to alleviate as much “bacterial noise” as much as possible

Also absent will be any CUC so my CA & trace element intake can be measured somewhat more accurately..emphasis on “somewhat”…

I get what you are saying about trying to run the system without huge amounts of bio-media. But I wouldn't obsess too much about thinking like you are growing corals in a sterile test tube. Even if you could, again - that would make it less applicable to the hobby. Growing corals in two parallel frag tanks with one variable at a time different between the two would be great info for hobbyists, again no need to try to treat the frag tanks like they are sterile test tubes.

That's my thoughts for now. Again, I love this.
-taricha (Jonathan)

 

[Doctorgori]

Also, I know what 6500K is, but I only sorta know what 28000K is supposed to mean - "really blue" - but you probably don't actually have a 28,000 Kelvin ball of plasma as a light source - so it'd be more informative to tell us what those two light sources actually are, and maybe post spectra of them if you have them handy.

Mitras Coral Pop

And Mitras Sky White

EDITED for correct graph (thanks/ credit RHF)

At first I wanted to find a LED with a broad sorta flat specral range similar to a ole skool 6500K MH…sorta a no peaks and valleys spread so the corals could pick and choose whatever to feed on, that way Im not introducing any preconceived biases on Chlorophyll A or theories on red light inhibition or whatever ..

I got side tracked on CRI for a second until bailed out by Oreo or Bean or someone like that (I started a thread, Ill fo look for it) …anyway, I got a TON of help from @oreo54 and will absolutely follow up with him on this…

At any rate it was a pipe dream to find or make a LED unit to duplicate anything close to a sunlight spectrum or anything close to imitate a Iwasaki 6500 without some serious Oreo customization..beyond my military grade slob a glob soldering skills

I settled on a Mitras bar…blame RHF for that suggestion …just got the invoice from GHL a few minutes ago..both units are in the mail supposedly

This whole exercise was driven by those ugly brown corals I used to keep in the 90’s…they grew but I always wondered if the colors were fixed in response to a suntan effect or was it just the 5500 lighting was not providing any inflorescence for lack of blue band energy …( pardon my spelling and lack of technical vernacular, its so bad my Terrance Howard Grammarly add on isnt working)

I truly want to see if there is something to providing a broad spectrum (from UV and out into the reds and IR);or if its just the imbedded spectrum already in those old MH ….

 

[Doctorgori]

Why try to drive all nutrition through phyto? That's not how most hobby systems run. It's hard to do and if you succeeded it would make your results harder to replicate for the hobbyist. Culturing phyto is a beast.
If phyto is a central part of something you are trying to do, then I suggest pre-fixed phyto products like these: https://reedmariculture.com/collections/instant-algae-feeds
These are frozen or refrigerated products that will last a long time, are plenty big for the scale you are using and are sufficient for fish rearing

Yeah, funny you said that…I bailed out Tuesday and ordered from Brine Shrimp Direct

Item	Qty	Retail Price	Discount	Unit Price	Extension
Product: Tahitian Blend Reef Tank Formula, 500 ml Catalog Number: TB500 Shipping Method: 2 via FEDEX 2 DAY- LOR _ COLD- (QTY 2-3)	2	$37.95	$0.00	$37.95	$75.90

​ Subtotal: $75.90 Shipping: $28.00 Tax: $0.00 Total: $103.90​ Payments​ 11/20/2024

The reason for a phyto only diet is so as to limit variables…No clue whats really driving colors, so I can’t go wrong with a phyto only diet since phytos nutritional profile is sorta known/ understood ….I also figured I could play with the different nutritional profiles of the assorted strains.,, see what shakes
…Problem is how to know how long after dosing when the effect on the color from the phyto kicks in. I may end up sticking with the concentrated blends or just culture the easy stuff like Nano, Iso and Tetraselmis (I got a rather stupid spell checker…pardon)

I was just going to dump pods into the tank, but no clue what sizes the sps could handle, so alternatively and in tandem I was going to gut load BBS with phyto and feed that to some Limias and let their poop deliver the nutrition (sorta like stuffing twinkies with vitamins) …

I was using converted fw Limias to mitigate saltwater biohazards, variable or whatever else…also to secondarily handle algae issues without the induced variable that a calcium sucking snail based CUC might add…

Pardon the Clevelandish and lack of scientific jargon…I could use a Swede like @Lasse for better English composition LOL

 

[Doctorgori]

I get what you are saying about trying to run the system without huge amounts of bio-media. But I wouldn't obsess too much about thinking like you are growing corals in a sterile test tube. Even if you could, again - that would make it less applicable to the hobby. Growing corals in two parallel frag tanks with one variable at a time different between the two would be great info for hobbyists, again no need to try to treat the frag tanks like they are sterile test tubes.

Almost forgot to add. One of the manufacturers has a “Probiotic” that supposedly aids in coral coloration…not certain if this can be proven or not but it would certainly be a cleaner look without a lot of bacterial background interference… I do realize this is near impossible but I can envision live rock, biomedia and similar adding unknown variables …

 

[Reefering1]

Imo, if trying to determine trace element correlation to color, and food is typically the main import of trace elements, this dictates you need to feed like a typical reef tank in typical circumstances. I imagine any addition would show improvements to a suffering coral vs one that has regular additions of traces via feeding. Ie- if you haven't ate in 2 weeks, 20 big macs might show improvement. But if you eat healthy food regularly, those 20 big macs will have a negative effect. Or am I looking at this completely wrong?

 

[MnFish1]

Almost forgot to add. One of the manufacturers has a “Probiotic” that supposedly aids in coral coloration…not certain if this can be proven or not but it would certainly be a cleaner look without a lot of bacterial background interference… I do realize this is near impossible but I can envision live rock, biomedia and similar adding unknown variables …

Every tank is going to have bacteria - and I don't think it's possible to ensure that tank A will have the same numbers or types as tank B (even though if I understood correctly, both tanks will have the same water column). I wonder if you need to feed phytoplankton at all? I would consider the commercial product - since at least hopefully, it will be consistent per lot (if you are going to feed anything). PS - do you have a length of time for the testing - and how often are you doing measurements. Since you have paired specimens - comparing survival might also be interesting.

 

[taricha]

This whole exercise was driven by those ugly brown corals I used to keep in the 90’s…they grew but I always wondered if the colors were fixed in response to a suntan effect or was it just the 5500 lighting was not providing any inflorescence for lack of blue band energy …( pardon my spelling and lack of technical vernacular, its so bad my Terrance Howard Grammarly add on isnt working)

I truly want to see if there is something to providing a broad spectrum (from UV and out into the reds and IR);or if its just the imbedded spectrum already in those old MH ….

The lighting effect is going to be really strong, and it'll be pretty easy to demonstrate.
here's the only lighting experimental data I'll have from my system. A couple of months ago I broke off a pocillopora, and threw it in my sump. Today, I broke off another piece and dropped it down there for comparison.

top pieces are the old ones that have lived in the sump under "white" LED for a couple of months, and the bottom left one is what has been in my tank under T5s with a blue lean to them.

If you want to see what's already been demonstrated about particular fluorescent proteins being increased by lighting at different colors, this Dana Riddle is a good place to start if you haven't seen it.

https://reefs.com/magazine/how-to-m...attention-to-blue-green-fluorescent-pigments/
https://reefs.com/magazine/how-to-m...and-photoconversion-from-green-to-orange-red/
https://reefs.com/magazine/how-to-m...ormation-red-fluorescent-pigments-dsred-type/

lots of charts like this...

The reason for a phyto only diet is so as to limit variables…No clue whats really driving colors, so I can’t go wrong with a phyto only diet since phytos nutritional profile is sorta known/ understood

A phyto-only diet definitely doesn't have fewer variables compared to keeping aquarium water at pretty typical NO3 & PO4 levels and supplementing with slight additions of phyto or aminos or whatever. This is especially true considering you are not running a full reef with a thousand mouths on every rock. You'll have accumulated uneaten phyto on the bottom and so have organics levels in the tank that will not be typical for most hobby systems.

 

[Doctorgori]

Imo, if trying to determine trace element correlation to color, and food is typically the main import of trace elements, this dictates you need to feed like a typical reef tank in typical circumstances. I imagine any addition would show improvements to a suffering coral vs one that has regular additions of traces via feeding. Ie- if you haven't ate in 2 weeks, 20 big macs might show improvement. But if you eat healthy food regularly, those 20 big macs will have a negative effect. Or am I looking at this completely wrong?

LONG, TL;DR warning (also some disorganized rambling)
But No, Ive been wrestling with similar thoughts:

One delay I have is writing this experiment is formulating a coherent organized outline and sequence for the experiments (thank you @taricha )

Another relevant write up is the equipment list, design and setup along with the day to day feeding/care/maintenance plan

Obviously I am not going to get away with not feeding anything, but in the same breath I fully expect algae issues in this unconventional setup, AND without CUC, this is going to be a problem….
… as will fueling the algae with 6500K lighting.

Fleshing this out for starters then,

1) What are the baseline nutritional needs of the corals besides the well established N & P levels? Put another way, is there a “all-in-one” compound we can add or what is the minimum combination of base “foods”? Can we get away with just adding Aminos and some phytoplankton blend? LOTS of products and claims out there, very little solid, precise info.

Do we know all the different pathways corals obtain extra nutrition outside of stealing from the host Zooxanthellae?

Since I personally don't know the prey capture methods or nutritional uptake methods for each type of coral in this study:

• I am limiting the coral genera in the experiment :
  • Acopora
  • Montipora
• Limiting the base nutritional input to just phytoplankton, either a blend or single species (TBD)
• “shotgunning” the nutrient delivery method (of the aforementioned phytoplankton blend via different trophic levels)
  • Direct live phytoplankton dosing
  • Direct feeding of copepods aquacultured by same phytoplankton blend
  • Indirect feeding by fish based CUC,
    • fish graze on pest algae (hopefully), and convert pest algae to feces
    • Fish directly predate on copepods
    • Fish fed gut loaded BBS (likewise aquacultured on same phytoplankton blend)

My thinking is limiting the variety of system nutritional input to phytoplankton and amino acids (at first anyway). Dose the amino acids per Tropic Marins instructions and in tandem maintain a robust copeopod population to “possibly” deliver the phyto by direct predation or indirectly via fish poop

Every tank is going to have bacteria - and I don't think it's possible to ensure that tank A will have the same numbers or types as tank B (even though if I understood correctly, both tanks will have the same water column). I wonder if you need to feed phytoplankton at all? I would consider the commercial product - since at least hopefully, it will be consistent per lot (if you are going to feed anything). PS - do you have a length of time for the testing - and how often are you doing measurements. Since you have paired specimens - comparing survival might also be interesting.

I fully agree with all you said and have had almost identical concerns, thoughts and ideas… expanding on this
and the quote below, this entire experiment needs a more detailed fleshing out…consider this conversation more evolution than argument…

A phyto-only diet definitely doesn't have fewer variables compared to keeping aquarium water at pretty typical NO3 & PO4 levels and supplementing with slight additions of phyto or aminos or whatever. This is especially true considering you are not running a full reef with a thousand mouths on every rock. You'll have accumulated uneaten phyto on the bottom and so have organics levels in the tank that will not be typical for most hobby systems.

Yes and agree to everything you said,

adding phyto is hardly a panacea with unused F/2 and the expected free floating and pest algae being a MAJOR concern.

I actually was going to start off just dosing the basic ALK, Ca, Mg thing along with aminos and see how that goes…

The whole phyto thing was to use as much live feed as possible in the “bath”. I didn't want the variable of uneaten food, et. I figured if I could establish growth with just phytos and aminos I could begin evaluating just the lighting and later perhaps test the assorted products and claims later…
Still fleshing this out, opinions VERY welcome

Also I did not want to gum up my alk/ca data with a lot of added growing CUC shells to deal with..maybe a VERY minor overthink, but Im on the fence with this still. I’m going to try Limias and see if they can manage algae a lil better amongst the eggcrate and acros. Freshwater fish aren't the best algae eaters but these are a saline tolerant/adapted species. I will see how it goes and/or if this species is the right choice… I did not want to use marine sourced fish as I sorta want to limit pest, parasites and any marine nasties into the system.

• I have twin Tunze refugium lights to power a macro reactor. not sure how this will affect trace elements or any bacterial variables. I am pretty certain a growing ball of chaeto will essentially be a nitrification area anyway. I just want to really limit porous surfaces and all the bacteria hub bub as a major influence/variable….
• As mentioned I have a 55W in line UV for the inevitable algae/bacterial bloom
• I have a schedule controllable/ DC Skimmer and pump for air exchange and to deliver Lanthanum chloride (at a scheduled time) if necessary
• The phyto is also on a dose pump for scheduled delivery (if we choose), UV can also be scheduled on/off to avoid interference

Again pardon the ramble, just thoughts to help you help me flesh this out …
Appreciate ANY input