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Bpb
07/08/2017, 07:54 AM
https://www.bulkreefsupply.com/video/view/turbocharge-photosynthesis-alkalinity-light-water-motion-by-dana-riddle-macna-2016/

The video in question linked above.

I watched this last night and it was really eye opening in a lot of ways. It confirmed some of my own observations regarding flow and alkalinity levels. It also revealed some science behind alkalinity that I didn't know. Corals using alkalinity not only for skeleton building, but also for the production of simple sugars from respiration was very interesting.

What blew me away the most was his discussion of lighting. Watch the video for the technical details, but from what I gather, his test specimens reached light saturation and photoinhibition MUCH lower than expected. Between 100-250 micromols of par. This is substantially lower than is typically recommended for an sps tank and most acropora.

Granted. He did his experiments on porites which most of us don't keep. But...my big question is this: he is determining saturation and photoinhibition in chlorophyll found in porites. Is that applicable across the board? Are the zooxanthellae and chloroplasts found in an acropora spathulata different from that found in porites? Or a lobophyllia for that matter? Is photoinhibition the same from coral to coral, but some with thicker or thinner tissues able to tolerate it and repair better from it?

I suppose I thought I understood light requirements but this video made it even more confusing. I understand higher light levels lead to more pigment productions which I understand help fight off the free radical byproducts of photosynthesis, but slow down photosynthesis at the same time. But would reducing our light levels in our acropora tanks to 100-200 par across the board "turbo charge" growth (even if it's at the sacrifice of color)?

Early in the video he also mentions fluorescence as inhibiting photosynthesis? Or am I not understanding that properly. If so then he would be suggesting a warmer spectrum to be much more growth promoting due to less fluorescence, despite all those blue wavelengths being important absorption peaks for photosynthesis.

Ideas?



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Orcus Varuna
07/08/2017, 08:34 AM
Very interesting Rusty I loved the video and would love to see experiments focusing on differences in epidermal thickness, enzyme composition and different species of zooxanthelli and how they affect the point at which photo inhibition is reached.


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ladynavyvet
07/08/2017, 08:36 AM
https://www.bulkreefsupply.com/video/view/turbocharge-photosynthesis-alkalinity-light-water-motion-by-dana-riddle-macna-2016/

The video in question linked above.

I watched this last night and it was really eye opening in a lot of ways. It confirmed some of my own observations regarding flow and alkalinity levels. It also revealed some science behind alkalinity that I didn't know. Corals using alkalinity not only for skeleton building, but also for the production of simple sugars from respiration was very interesting.

What blew me away the most was his discussion of lighting. Watch the video for the technical details, but from what I gather, his test specimens reached light saturation and photoinhibition MUCH lower than expected. Between 100-250 micromols of par. This is substantially lower than is typically recommended for an sps tank and most acropora.

Granted. He did his experiments on porites which most of us don't keep. But...my big question is this: he is determining saturation and photoinhibition in chlorophyll found in porites. Is that applicable across the board? Are the zooxanthellae and chloroplasts found in an acropora spathulata different from that found in porites? Or a lobophyllia for that matter? Is photoinhibition the same from coral to coral, but some with thicker or thinner tissues able to tolerate it and repair better from it?

I suppose I thought I understood light requirements but this video made it even more confusing. I understand higher light levels lead to more pigment productions which I understand help fight off the free radical byproducts of photosynthesis, but slow down photosynthesis at the same time. But would reducing our light levels in our acropora tanks to 100-200 par across the board "turbo charge" growth (even if it's at the sacrifice of color)?

Early in the video he also mentions fluorescence as inhibiting photosynthesis? Or am I not understanding that properly. If so then he would be suggesting a warmer spectrum to be much more growth promoting due to less fluorescence, despite all those blue wavelengths being important absorption peaks for photosynthesis.

Ideas?



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😯, when I purchased my LED light bar I just went to my lfs, and after a quick review of the livestock in my tank, and my budget for lighting for my tank, I purchased what they recommend. Previously to this, I just thought about lighting from a photographer's viewpoint. For example, I was at a country music concert a week ago, and was having a devil of a time getting any decent shots of the artists, until I realized the lighting temperatures on stage was way hotter than the white balance setting on my phone in automatic camera mode on my phone. Once it was reset, the difference was huge.
I have to wonder if there's a basic explanation of tank lighting on RC? Recommendations for lighting, based on needs, depth of tank, and budgets?

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fscmocsaj
07/08/2017, 08:44 AM
Way too many big words for me to comprehend


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Orcus Varuna
07/08/2017, 09:11 AM
Way too many big words for me to comprehend


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🤦🏼*♂️


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Bpb
07/08/2017, 09:12 AM
[emoji54], when I purchased my LED light bar I just went to my lfs, and after a quick review of the livestock in my tank, and my budget for lighting for my tank, I purchased what they recommend. Previously to this, I just thought about lighting from a photographer's viewpoint. For example, I was at a country music concert a week ago, and was having a devil of a time getting any decent shots of the artists, until I realized the lighting temperatures on stage was way hotter than the white balance setting on my phone in automatic camera mode on my phone. Once it was reset, the difference was huge.
I have to wonder if there's a basic explanation of tank lighting on RC? Recommendations for lighting, based on needs, depth of tank, and budgets?

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I think the spirit of the video is that it's a lot more common that we over light our tanks rather than the opposite targeting light ranges and spectrum seems to be more beneficial than recommending for or against specific fixtures. Unfortunately many of us don't own par meters


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jda
07/08/2017, 09:24 AM
You can grow porites, montis and poci in fuges under screw-in CFL bulbs. I would not look for this video to scale much to what folks want to keep.

Just a basic thought that corals would not grow out of the water in low tide if they did not want as much sun as they could get... there are deeper places to grow if they just wanted to filter feed from the current.

Bpb
07/08/2017, 09:33 AM
Fair enough. I was kind of looking for something more than "don't pay attention to that video" or what I expect coming "look at my, or 'X's' tank under 700 par and it looks great". I'm more concerned with some actual science, even if it's somewhat translated to a layman. I feel like he touched on some important concepts and made some stiff claims and recommendations, but glossed over some details


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Orcus Varuna
07/08/2017, 06:39 PM
Fair enough. I was kind of looking for something more than "don't pay attention to that video" or what I expect coming "look at my, or 'X's' tank under 700 par and it looks great". I'm more concerned with some actual science, even if it's somewhat translated to a layman. I feel like he touched on some important concepts and made some stiff claims and recommendations, but glossed over some details


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I completely agree... The fact remains that ALL corals are cnidarians utilizing symbiotic dinoflagellates to photosynthesis for them inorder to complete respiration and provide energy to the host coral in the form of ATP. Just because his experiment was on Porites sp. does NOT change this fact. I too would love some input on how different genus and species of corals cope with higher intensity lighting and to what effect should we look to balance overall coloration with coral health. What makes an Acropora have the ability to roast under 600+ PAR and retain chlorophyll but certain chalices would bleach in 2 days? Is it enzymatic differences, epidermal thickness, accessory pigments, etc? And whatever coping mechanisms they posses how do these effect the ideal PAR level?

Thank you for bringing up a question that attempts to ask people to think for once on this forum. Now let's see if we can get some thought provoking responses...


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madweazl
07/08/2017, 06:52 PM
You can grow porites, montis and poci in fuges under screw-in CFL bulbs. I would not look for this video to scale much to what folks want to keep.

Just a basic thought that corals would not grow out of the water in low tide if they did not want as much sun as they could get... there are deeper places to grow if they just wanted to filter feed from the current.

I'm not sure what led you to this conclusion, can you elaborate?

jda
07/08/2017, 10:27 PM
When I still live in Missouri, I grew acropora outside in a tub on summer in about one foot of water under the sun. In four months, I grew a Red Planet and Cali Tort as big as cantaloupes. I also grew a Hollywood Stunner (back when these were kinda cool) that got so big that I had to just give away since it would not even fit in a 40 breeder - you could measure new growth every day and I had to add a second calcium reactor. The system was connected to my main reef (the only way that I could keep it cool outside). Frags in the frag tank in the same system under MH grew to about baseball size in this same timeframe. The only thing that was different was the light.

This does not stop at stonies. I grow bounce mushrooms to sell (a great way to fund a hobby) and I grow them in a frag tank about 6" under a 250W 20K radium and they can grow from nickel size to about 3" across in about four months. Zoas too. They grow so much faster under high output than they do under less.

I have no studies or science and it is too bad that the ones that we do have are on coral that can be kept with the absolute lowest care requirements, but I cannot believe with any piece of my experience that more high quality light is not better for nearly all corals than less.

To me, I throw this study out wholesale. It is as much as a waste as the one that concluded that activated carbon absolutely causes HLLE in fish - that study was also biased with tangs that nobody would keep in captivity and never exposed what they fed the fish which most can actually attribute to HLLE. There is significantly too much hobby related experience that is the exact opposite to conclude that either of these are on the money. Are they worth a read, sure. Riddle could have at least found some Montis or Birdsnest, even those are like weeds too. I could have donated him ten pounds of green slimers or cali tort.

Bpb
07/08/2017, 10:36 PM
I appreciate your input and generally always value your experience in your posts. I'm curious about the why though. Why does he hypothesize that all corals EXCEPT acropora tend to grow faster under high alkalinity conditions. And what about acropora in particular make them less subject to photoinhibition. Is it something that is measurable and applicable on the hobbyist end. Ultimately i guess everyone would appreciate doing more with less. But most of all I am intrigued as to why acropora are different in these sets of rules. Not so much need convincing that acros like lots of light.


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jda
07/08/2017, 10:48 PM
I am not sure about the alk. I keep all of my frag tanks and fuges on my SPS system and try and keep the water as close to NSW as it gets... 1.026, .01P, .1N, 78-79 degrees, 7.4-7.7 alk, 425-435 calcium. The softies grow in my tank as fast as anything. LPS are crazy too but I don't keep many of them since it breaks my heart to frag them up (some don't like it very much like my favorite fox corals and wall hammers). I guess that my point is that everything thrives. I am VERY stable, which I imagine helps.

I have no real theories on this, but I have to believe that if natural selection choose these specimens to live in NSW conditions, then should that not be the best?

Anecdotally, I have found that trace elements are VERY important to all coral moreso than acropora. My higher end zoas will stop growing like crazy if I slow down on water changes. They don't recede or die or anything, but the calcium reactor input is not enough to make them happy - there is something in the salt. The acropora do not mind at all even though the softies get mad.

I have never found that higher alk slows my acropora growth down. I just like to keep it low since if my P and N get any lower, the skeleton will outgrow the tissue and I get burnt tips. I don't do much to control the N and P now and I don't want to add anything, so keeping the alk low at NSW levels keeps calcification in check a bit and it all works out without much effort.

Even if folks don't agree with my opinion that corals grow out of the water because they are looking for light, these photos are well worth a look just to awe over them. They are pretty cool:
http://www.placestoseeinyourlifetime.com/the-great-barrier-reefs-gardens-at-low-tide-in-australia-5312/

Bpb
07/08/2017, 11:48 PM
Love those pictures indeed.


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Orcus Varuna
07/09/2017, 06:47 AM
Like Rusty I just want to know the why behind what makes Acropora sp. more capable to cope with 350+ umol of light. If only I was still in college this would be a wonderful thesis project. I will reach out to some old professors and see if I can get any takers.


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Bpb
07/10/2017, 09:52 AM
http://www.advancedaquarist.com/2012/12/corals

This article answered a lot of my questions and makes sense of your experiences JDA


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jda
07/10/2017, 09:12 PM
Two things amaze me as I re-read that article.

1). It is by the same guy as the video in the first post.
2). That is where I started to base my theory that LEDs lacking UV down to 350 is probably why they don't color coral as well - one reason anyway. The excitation level of all pigments in the study are at 350 or lower. I totally wish that he would have shown the emission of light from 400 to 700... there could be a lot of emission missing... but another test for another day.

Bpb
07/10/2017, 09:38 PM
Yeah it's by Dana riddle only difference like you pointed out the previous one was in regards specifically to porites sp. in Hawaiian specific tide pools on an experiment he did alone. As opposed to the second which was a conglomeration of several studies on dozens of acropora


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Orcus Varuna
07/11/2017, 10:00 PM
Yeah it's by Dana riddle only difference like you pointed out the previous one was in regards specifically to porites sp. in Hawaiian specific tide pools on an experiment he did alone. As opposed to the second which was a conglomeration of several studies on dozens of acropora


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@Bpb as we were discussing the other day I am nearing 100% sold on the 6500k bulbs either in a t5 loadout or as a supplemental light source to the the hyper blue schedules most LED of us led users run. The 6500k lamps really do have almost everything spectrum wise outside of UV-B. At the low peak they even capture a bit of UV-A radiation. But as @JDA brought up, the excitation phase of the chromatoprotiens we a looking for an increased expression of seem to be activated all the way down to near UV-C spectrum. So this begs the question does a true UV bulb such as the ones marketed for reptiles potentially have a place in somewhere in our bulb configurations?



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jda
07/11/2017, 10:11 PM
You are going to find lots of UV down to 350 in 10K MH bulbs and the URI T5 and especially their VHO bulbs. I am not familiar with this Tropic 6500K bulb, so not sure if you are a MH or T5 guy. I don't think that you need a reptile bulb to get some of this. The old school light sources have had UV for a long time.

I don't know whether they lucked into their bulbs a few decades ago, or are really smart, but UVL gets it and always have some UV in them. They also test and show a chart below 400nm. See if you can find one that you like on here, but I recommend the Actinic White:
http://www.uvlco.com/AquariumT5.html

Bpb
07/12/2017, 12:23 AM
I did love running metal halides. Especially 10k XM's. Wish I hadn't gotten rid of them


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graham hunt
07/12/2017, 07:32 AM
You are going to find lots of UV down to 350 in 10K MH bulbs and the URI T5 and especially their VHO bulbs. I am not familiar with this Tropic 6500K bulb, so not sure if you are a MH or T5 guy. I don't think that you need a reptile bulb to get some of this. The old school light sources have had UV for a long time.

I don't know whether they lucked into their bulbs a few decades ago, or are really smart, but UVL gets it and always have some UV in them. They also test and show a chart below 400nm. See if you can find one that you like on here, but I recommend the Actinic White:
http://www.uvlco.com/AquariumT5.html
Hi jda,if I could jump in with a question,I run 400w radiums in guismann infinity fixtures with a dimtec glass shield supposedly uv and heat (ir) blocking,I have run the lights without shield using ushio/blv lamps which on lamps say are uv protected I assume glass envelope is made so.the radium instructions suggest
The lamps are not shielded and require a separate shield so I have been wary of not using it,it would seem from latest info uv could be usefull,heat for my situation is not a problem so I would appreciate your thoughts on using the shield or not with radius,mounting height is 10 jnches above water line.
Regards graham.

jda
07/12/2017, 08:53 AM
The glass on SE bulbs filter out most UV in the low 300s - at least enough to be harmless. There is still UV in there. You don't need to use any extra glass for the ones that I know about. I take the glass out of all of my SE stuff to get the extra output.

A DE bulb absolutely has to have the glass shield or else you can do significant UV damage to your inhabitants.

graham hunt
07/12/2017, 09:12 AM
Thank you jda,that puts my mind at rest,with luck a bit more spectral output,I will remove glass and watch to see if colour changes.
Regards graham.

Bpb
07/12/2017, 09:52 AM
Also I want to chime in. UVB and ESPECIALLY UVC are absolutely known to cause various forms of skin cancer and cataracts under prolonged exposure, such as a situation of an open top tank with no canopy where you are constantly exposed to a direct beam. Definitely use glass shielding on double ended bulbs which lack the tempered glass shield mogul bulbs enjoy. Any hypothetical gains in coral health aren't worth risking your own or your family's


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graham hunt
07/12/2017, 10:33 AM
Also I want to chime in. UVB and ESPECIALLY UVC are absolutely known to cause various forms of skin cancer and cataracts under prolonged exposure, such as a situation of an open top tank with no canopy where you are constantly exposed to a direct beam. Definitely use glass shielding on double ended bulbs which lack the tempered glass shield mogul bulbs enjoy. Any hypothetical gains in coral health aren't worth risking your own or your family's
Again thanks for the head up,as you say de are very tricky,ushio/blv se state on
Glass uv protected but not radium which in an open view no canapy situation is
Worrying,might not be worth the risk for perceived gain.think I may wait till I can find blv 14k which is proving a bit hard in U.K. Presently.
Regards graham.

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