Light, Alkalinity, Nutrients.

[Dana Riddle]

Wijgerde saw problems with Stylophora pistillata at 100 micrograms per liter zinc. Triton's test reported zinc at ~175% of true value (according to Ross in reefs.com), so even with ICP testing now available it seems to be difficult to know what the level of zinc actually is but it seems certain that low and high concentrations can cause issues with zooxanthellae. So, to answer your question about zinc dosing and algal filtration... I don't know.

 

[mcarroll]

My brain hurts.

On the page you see when you first click the link, I do try to provide some "cliff's notes" of the article which are pretty much in reef language. That might be all you need, and if it turns out to be very interesting you can grit your teeth, click through and read the whole article.

FYI...

If you haven't looked at journal articles before, I highly recommend skipping all the parts that make your eyes cross and have a great conscience about doing it.

Don't get hung up on anything that isn't immediately making sense – skip to the next section and try reading some more. Most of the article is going to be written for other scientists, so this is to be expected. Skip away! Sometimes all you need is the Abstract and the Conclusions or Results anyway.....those parts are usually in plain english.

Of course ask questions about anything you want to – don't skip the whole article if you don't understand anything!

2¢

 

[TbyZ]

On the page you see when you first click the link, I do try to provide some "cliff's notes" of the article which are pretty much in reef language. That might be all you need, and if it turns out to be very interesting you can grit your teeth, click through and read the whole article.

FYI...

If you haven't looked at journal articles before, I highly recommend skipping all the parts that make your eyes cross and have a great conscience about doing it.

Don't get hung up on anything that isn't immediately making sense – skip to the next section and try reading some more. Most of the article is going to be written for other scientists, so this is to be expected. Skip away! Sometimes all you need is the Abstract and the Conclusions or Results anyway.....those parts are usually in plain english.

Of course ask questions about anything you want to – don't skip the whole article if you don't understand anything!

2¢

Thanks.

My brain hurt from reading the conflicting views in the thread.

 

[TbyZ]

Wijgerde saw problems with Stylophora pistillata at 100 micrograms per liter zinc. Triton's test reported zinc at ~175% of true value (according to Ross in reefs.com), so even with ICP testing now available it seems to be difficult to know what the level of zinc actually is but it seems certain that low and high concentrations can cause issues with zooxanthellae. So, to answer your question about zinc dosing and algal filtration... I don't know.

Measuring zinc in the home aquarium is difficult & considering the overwhelming of dismutase enzymes by oxygen radicals via high alk turbocharged photosynthesis it seems logical to keep alk levels more natural.

What about dosing non zinc SOD tablets used for human consumption?

 

[Dana Riddle]

I learn something every day - wasn't aware SODs were available in capsule form. I looked at a couple of ads, and these didn't say if the enzymes had copper, manganese, iron, or zinc backbones, but didn't do an exhaustive search by any means. Years ago, Albert Thiel recommended adding another antioxidant to reef aquaria - vitamin C - and instantly started a rather nasty flame war. However, Craig Bingman came to his defense with positive thoughts on this supplement.
If we subscribe to the hypothesis that high alk does indeed cause tip burn due to high rates of photosynthesis, I would think that we could use this information to manipulate parameters to our advantage (such as promoting photosynthesis in low light conditions.) Just thinking out loud...

 

[mcarroll]

It would be an interesting experiment to dose zinc because there's nothing about this hobby that isn't interesting.

But I have to admit that I'm having trouble imagining that GFO, carbon source dosing and "ULNS" are all just coincidence in "burnt tips tanks" and somehow all these folks are all coincidentally deficient in Zn of all things and that's the cause.

• Check post #5 on another thread where this guy was found "deficient" in zinc on a Triton test and "wanted to dose zinc" thanks to Triton's guidance, but in the same breath he noted that his burnt tips were already healing too.
• Later (#20) he claims even after dosing zinc (and showing Triton results indicating positive levels) that his tips are still problematic.
• All the while he's getting advice to keep pounding his already-infinitesimal level of 0.018 ppm of PO4 into the dust.
• Shortly after that the advice shifts to check nutrients (and nitrates too! ) and then the OP notices that his ATS has stopped working. ;Penguin

Like I said the zinc angle is certainly interesting to think about, and to experiment with in the event that you have burnt tips.

At the same time though it seems like we/they are avoiding several more-likely explanations for burnt tips in order to look at an explanation which is possible but which seems much less likely – maybe even improbable.

Did anyone else already know that apparently some planted tank folks dose organic carbon in lieu of CO2 and plants respond similarly? I literally just found out, so maybe there's more to the story.

But I had been under the misimpression from some pro-level guidance I read a while back* that these two carbon sources were not interchangeable for photosynthesis. If that guidance was just an assumption and in fact they are interchangeable, then I think this goes to my theory that even CO2 dosed tanks – so maybe all carbon-dosed tanks – seem to be more susceptible to burnt tips.

I started collecting data on this a while back but got distracted....anyone have a list of users who've already had (and documented) their case of burnt tips?

If you have burnt tips in your tank now, please PM me. Seriously!

* I immediately googled and found out that carbonic anhydrase exists (;Shamefullyembarrased) and that it converts carbon dioxide from inorganic to organic (and back) at lightning speed. But I didn't know much else about it – perhaps carbonic anhydrase just didn't work like that – so I assumed the guidance wasn't wrong. Oh well.

 

[Dana Riddle]

There are internal and external carbonic anhydrases (ECH) - bicarbonate doesn't pass through cellular membranes as easily as CO2, so it *might* be that quickly growing corals would possess ECH as a means of obtaining inorganic carbon in a favorable fashion for photosynthesis. It seems tip burn has been reported on fast-growing branching corals...

 

[poorish idol]

wow...you guys sound like scientists!!!! suoer knowledgeable...and Interesting...but the complication is making me feel hopeless..and wanting out of the hobby again!!! lol. I've personalmy have seen success with both uln and high nutrient for a long period of time. but I agree that it's probably best to lean towards more nutrients as to prevent swings. as we all know, consistency and stability of Params is key...so it is easier to get your sps used to some nutrients so they can adapt to changes better. I personally like to keep my phos at .03 and nitrates at 25...thsnk you guys for your input....felt like I just sat thru an advance chemistry class..

 

[taricha]

I'll take a look - thanks! Zinc is one of the metals in the SOD antioxidant enzymes that detoxify the oxygen radicals produced by photosynthesis. This fits nicely with my thought that amplified photosynthesis due to high inorganic carbon is the cause of tip burn.

Unsure if it's been stated out loud but the lighter colored tips on a coral indicates a lack of the fluorescent protein sunscreen that the rest of the coral colony has produced. So if too much photosynthetic activity / reactive oxygen is indeed the culprit, there's good reason the tips show the damage.

 

[mcarroll]

This is complicated......

The tips are also white due to a lack of dino's....so no (or almost no) photosynthesis there.

There's also the issue of branching structure and self-shading. They (branching corals) seem to design themselves so that the tips take almost all the sun's light....the further down the branch you go, the lower the irradiance levels are.....I think I've read that the bases of branches are like 60-70% shaded compared to the tips.

 

[Dana Riddle]

With the new lab functional and the coral tank running, I am now able to being new testing (thanks to everyone who contributed to the lab fund!) I'm looking at chlorophyll content of Acropora white tips and brown bases. My results are much different than the 1989 Feng et al paper, suggesting (and I'll beat the dead horse) an aquarium is not the ocean, and the ocean is not an aquarium. This is going to get rather involved, so I'll publish the results (with photos and charts) when it's all said and done.

 

[Dana Riddle]

There are internal and external carbonic anhydrases (ECH) - bicarbonate doesn't pass through cellular membranes as easily as CO2, so it *might* be that quickly growing corals would possess ECH as a means of obtaining inorganic carbon in a favorable fashion for photosynthesis. It seems tip burn has been reported on fast-growing branching corals...

That should be "been reported only on fast-growing branching corals..."

 

[Ashish Patel]

All we know for sure is that corals need these 3 things to satisfy the corralites as well as zooxanthellaes.... Corals build their bones with the available calcium carbonates and their zooxanthellae use nutrients/Light/photosynthesis. The ratio in nature is low nutrients, low ALK, and Low to high lighting; everything grows in a balanced way because corals comprise of 2 animals - If one is growing faster then the other how will this work?

I would imagine people with the lacking growth with SPS should look at balancing these 3 things. By default I run Low nutrients but as my tank matures id prefer to run the tank at the mid-level point as this will give me more room for error. High nutrients needs more ALK, Low nutrients need less Alk and less lighting.. Once we figure this out we can finally have success

 

[BoomCorals]

I have one coral in particular that if I let my alk go up past about 9.5, the frags will STN almost like clockwork. My nitrate and phosphate are around 1-2ppm and .03-.05 respectively. PAR is around 300 for where I keep these frags.

 

[Mattyice008]

Bump. Been about a year since last post, but I learned a lot reading through it. Anyone else have input on the initial question?

 

[mcarroll]

I have one coral in particular that if I let my alk go up past about 9.5, the frags will STN almost like clockwork. My nitrate and phosphate are around 1-2ppm and .03-.05 respectively. PAR is around 300 for where I keep these frags.

Low N is much better adapted for than low-P, and those light levels would probably stress the need for P.

I'm betting that your sensitive coral (from September 2017 ) had a relatively low ability for PO4 acquisition...perhaps due to genetics or some other environmental factor. (Light and nutrients aren't the whole picture after all.)

I'd love to experiment with the same coral in another system.

Check out Phosphate deficiency promotes coral bleaching and is reflected by the ultrastructure of symbiotic dinoflagellates. This is one of the key graphics from the article: (H=high L=low N=nitrogen P=phosphate; colums are macro photo, skin sample, dino's from skin sample.)

 

[madweazl]

Excellent article, thanks for sharing.

 

[Coral Euphoria]

I'd like to hear your thoughts of the relationships of these 3 parameters. For example, I've seen recommendations to adjust nutrient levels upwards if running high alkalinity, which seems to defy Liebig's Law of the Minimum which states the rate of photosynthesis is regulated by the least available nutrient, not the most abundant. In other words, alkalinity, acting as the carbon source for photosynthesis, doesn't matter if phosphorus is the limiting factor. Unless you're suggesting alkalinity has an effect unrelated to photosynthesis.

I know this is an old thread, but I got lost on all the tangents and how complicated the discussion got. But did we ever come to a consensus or did you start a new thread?

But regarding your original question.. Could it be that it is actually the other way around? Instead of running high nutrients if you are running higher alk, could it be the recommendation is actually: If you are running higher nutrients, you should have higher alk? Maybe the statement got flipped around?

If so, RHF talks about it in his nitrate article:

"In most cases where nitrate levels have been examined in relation to the growth of calcareous corals, the effects have been reasonably small, but significant. Elevated nitrate has been shown to reduce the growth of Porites compressa (at less than 0.3-0.6 ppm nitrate),16,17 but the effect is eliminated if the alkalinity is elevated as well (to 4.5 meq/L). One explanation is that the elevated nitrate drives the growth of the zooxanthellae to such an extent that it actually competes with the host for inorganic carbon (which is used both in photosynthesis and in skeletal deposition). When the alkalinity is elevated, this competition no longer deprives the host of needed carbon.17"

article:

Nitrate in the Reef Aquarium

Introduction Nitrate is an ion that has long dogged aquarists. It is typically formed in aquaria through the digestion of foods, and in many aquaria it builds up and can be difficult to keep at natural levels. In the past, many aquarists...

www.reef2reef.com

I could be missing the point (especially since it's 3am), but could this simply be the relationship between alk and nutrients?

--------

As for the relationship between Light and Nutrients, hasn't this been revealed in the paper, Phosphate deficiency promotes coral bleaching and is reflected by the ultrastructure of symbiotic dinoflagellates,

where they state that HN/LP made corals more susceptible to light/heat stress? Where they said that corals in the LN/LP, HN/HP, or LN/HP, did fine, but the HN/LP were unhealthy? Would this be the relationship between light and nutrients?

Article:

Checking your browser - reCAPTCHA

---------

I'm probably missing something...

 

[RevMH]

I know this is an old thread, but I got lost on all the tangents and how complicated the discussion got. But did we ever come to a consensus or did you start a new thread?

But regarding your original question.. Could it be that it is actually the other way around? Instead of running high nutrients if you are running higher alk, could it be the recommendation is actually: If you are running higher nutrients, you should have higher alk? Maybe the statement got flipped around?

If so, RHF talks about it in his nitrate article:

"In most cases where nitrate levels have been examined in relation to the growth of calcareous corals, the effects have been reasonably small, but significant. Elevated nitrate has been shown to reduce the growth of Porites compressa (at less than 0.3-0.6 ppm nitrate),16,17 but the effect is eliminated if the alkalinity is elevated as well (to 4.5 meq/L). One explanation is that the elevated nitrate drives the growth of the zooxanthellae to such an extent that it actually competes with the host for inorganic carbon (which is used both in photosynthesis and in skeletal deposition). When the alkalinity is elevated, this competition no longer deprives the host of needed carbon.17"

article:

Nitrate in the Reef Aquarium

Introduction Nitrate is an ion that has long dogged aquarists. It is typically formed in aquaria through the digestion of foods, and in many aquaria it builds up and can be difficult to keep at natural levels. In the past, many aquarists...

www.reef2reef.com

I could be missing the point (especially since it's 3am), but could this simply be the relationship between alk and nutrients?

--------

As for the relationship between Light and Nutrients, hasn't this been revealed in the paper, Phosphate deficiency promotes coral bleaching and is reflected by the ultrastructure of symbiotic dinoflagellates,

where they state that HN/LP made corals more susceptible to light/heat stress? Where they said that corals in the LN/LP, HN/HP, or LN/HP, did fine, but the HN/LP were unhealthy? Would this be the relationship between light and nutrients?

Article:

Checking your browser - reCAPTCHA

---------

I'm probably missing something...

Interesting. I'd like to follow along for an update from the experts. Good stuff here, even if the original forum date is older.

 

[arking_mark]

I know this is an old thread, but I got lost on all the tangents and how complicated the discussion got. But did we ever come to a consensus or did you start a new thread?

But regarding your original question.. Could it be that it is actually the other way around? Instead of running high nutrients if you are running higher alk, could it be the recommendation is actually: If you are running higher nutrients, you should have higher alk? Maybe the statement got flipped around?

If so, RHF talks about it in his nitrate article:

"In most cases where nitrate levels have been examined in relation to the growth of calcareous corals, the effects have been reasonably small, but significant. Elevated nitrate has been shown to reduce the growth of Porites compressa (at less than 0.3-0.6 ppm nitrate),16,17 but the effect is eliminated if the alkalinity is elevated as well (to 4.5 meq/L). One explanation is that the elevated nitrate drives the growth of the zooxanthellae to such an extent that it actually competes with the host for inorganic carbon (which is used both in photosynthesis and in skeletal deposition). When the alkalinity is elevated, this competition no longer deprives the host of needed carbon.17"

article:

Nitrate in the Reef Aquarium

Introduction Nitrate is an ion that has long dogged aquarists. It is typically formed in aquaria through the digestion of foods, and in many aquaria it builds up and can be difficult to keep at natural levels. In the past, many aquarists...

www.reef2reef.com

I could be missing the point (especially since it's 3am), but could this simply be the relationship between alk and nutrients?

--------

As for the relationship between Light and Nutrients, hasn't this been revealed in the paper, Phosphate deficiency promotes coral bleaching and is reflected by the ultrastructure of symbiotic dinoflagellates,

where they state that HN/LP made corals more susceptible to light/heat stress? Where they said that corals in the LN/LP, HN/HP, or LN/HP, did fine, but the HN/LP were unhealthy? Would this be the relationship between light and nutrients?

Article:

Checking your browser - reCAPTCHA

---------

I'm probably missing something...

Great thread, but let's chase some #s

If these are the general principles:
1. Low P (phosphorous limited) higher PAR leads to bleaching
2. High N (Nitrogen rich) lower Alk leads to reduced growth and browning

ULNS should have lower PAR and lower Alk.

High N / Low P systems should have lower PAR and higher Alk.

Low N / High P systems should have higher PAR and lower Alk

High N / High P systems should have higher PAR and Higher Alk

So the question is what are the values for (SPS, LPS, Softies):
Low P
High P
Low N
High N
Lower Alk
Higher Alk
Lower PAR
Higher PAR

???