It's Still in the Water!
- Thread starter cfockler
- Start date
Hi,
At this time, I would like to summarize a bit, and close the thread. If anybody wants to continue the discussion, then do it elsewhere; every time somebody posts here it sends an email to me and that is getting to be significantly annoying.
Randy has made the point that organic materials are present in tanks and likely detoxifying metals. However, he cannot give any specifics about this process, nor has any work on this been done.
That notwithstanding, such detoxification seems likely, at least at times.
Habib has mentioned some of the tests showing detoxification.
I have tested and found high overabundances of metals in tank waters, whether or not they are bound in organic materials or free as ions. Similar tests on sea water or in aquaria dosed with chemicals to levels lower than in that what I have found have resulted in death of corals, snails, and sea anemones.
Presently, the result of this metals overabundance is unclear. I think it is cause for concern. Randy doesn't. He likes 'em.
I think it is unlikely that any further discussion in this thread will resolve anything, or change any opinions, so I am closing it. As I said above if you wish to carry on the discussions elsewhere open a new thread.
At this time, I would like to summarize a bit, and close the thread. If anybody wants to continue the discussion, then do it elsewhere; every time somebody posts here it sends an email to me and that is getting to be significantly annoying.
Randy has made the point that organic materials are present in tanks and likely detoxifying metals. However, he cannot give any specifics about this process, nor has any work on this been done.
That notwithstanding, such detoxification seems likely, at least at times.
Habib has mentioned some of the tests showing detoxification.
I have tested and found high overabundances of metals in tank waters, whether or not they are bound in organic materials or free as ions. Similar tests on sea water or in aquaria dosed with chemicals to levels lower than in that what I have found have resulted in death of corals, snails, and sea anemones.
Presently, the result of this metals overabundance is unclear. I think it is cause for concern. Randy doesn't. He likes 'em.
I think it is unlikely that any further discussion in this thread will resolve anything, or change any opinions, so I am closing it. As I said above if you wish to carry on the discussions elsewhere open a new thread.
Well, gosh, golly, gee, Randy. That's why I asked you to discuss them.
No, actually it's not. You asked because you were accusing me of overgeneralizing, thinking that I was generalizing about humic acids and did not have any specific info (reread your own post if you doubt that). I was being as specific as is possible with a class of substances. Hence my response. If I thought you were genuinely interested in knowing more about what humic substance that I was referring to, I would certainly not have responded that way.
No, actually it's not. You asked because you were accusing me of overgeneralizing, thinking that I was generalizing about humic acids and did not have any specific info (reread your own post if you doubt that). I was being as specific as is possible with a class of substances. Hence my response. If I thought you were genuinely interested in knowing more about what humic substance that I was referring to, I would certainly not have responded that way.
However, he cannot give any specifics about this process, nor has any work on this been done.
I thought that both Eric and I pointed out that a great deal of published work has been done on the toxicity of copper and it's speciation. On corals in reef tanks? No. Do you have any tox data on corals in reef tanks? No.
So we both fall back on what is known: that metals can be toxic to many organsims in many situations, and that binding by organics has been demonstrated to play a role in some of those situations. Hence, my assertion that organics MAY play a role in reef tanks, and that the situation may not be as dire as you claim when you flatly state that we are killing corals.
I thought that both Eric and I pointed out that a great deal of published work has been done on the toxicity of copper and it's speciation. On corals in reef tanks? No. Do you have any tox data on corals in reef tanks? No.
So we both fall back on what is known: that metals can be toxic to many organsims in many situations, and that binding by organics has been demonstrated to play a role in some of those situations. Hence, my assertion that organics MAY play a role in reef tanks, and that the situation may not be as dire as you claim when you flatly state that we are killing corals.
You say the yellow color is indicative of them. I say, it could just as well be saffron yellow in coral pee.
Actually, if you feed saffron to your tank, it probably is part of the problem. For the remainder of us, I'll accept the comments by marine chemists and biochemists, as referenced in Spotte that
"The main refractory component consists of humus, a portion of which imparts yellow coloration to old aquarium seawater".
Do you think that these scientists are wrong? Or do you just find it easy and convenient to say that these ideas are my imagination, and forget that there is published literature to support it?
Actually, if you feed saffron to your tank, it probably is part of the problem. For the remainder of us, I'll accept the comments by marine chemists and biochemists, as referenced in Spotte that
"The main refractory component consists of humus, a portion of which imparts yellow coloration to old aquarium seawater".
Do you think that these scientists are wrong? Or do you just find it easy and convenient to say that these ideas are my imagination, and forget that there is published literature to support it?
Well Randy,
The reason I asked if you had any specific data, to which you showed that you didn't, is that I was wondering if you personally actually had any numerical data to draw on, or if you were simply blowing in the wind.
Perhaps, I should explain that I didn't quite fall off the turnip truck with regard to these chemicals; I have had to use data on them in a number of projects, and some of them, at least, are easily tested for. Incidently, in really high concentrations, they are no longer yellow; they can be purple, black and ochre.
You see, there is a significant body of data regarding the some of these organics in both aquaria and the real world. And there is actually some information about them in coral reef situations, in areas downstream of logging sites.
In specific, in the Pacific NW, and probably elsewhere in the US, some of the major pollutants are pulp mills, and signficant amount of their pollution would be classified as humic acids, and similar kinds of organics. The EPA maintains a list of "Priority Pollutants" to be tested for in pulp mill remediation, etc. Included in this list are a reasonably large number of these types of organics. Data do exist for them with regard to their toxicity toward all sorts of organisms.
Now, are these chemicals the same ones found in our tanks? Maybe, but more likely, maybe not. However, certainly some chemicals characteristic of the various classes of them are. And then, contrarty to your assertions that they can't be examined and must be treated as a "black box," it appears that they can be examined and analysed, at least as first step.
If some of the chemicals on the EPA's priority pollutent list could be considered representative of some of the classes of these organics, then we could test for them in aquaria, and we could look at their effects. Analytical labs, such as the one I used for my metals studies, also routinely examine these pollutants. I am not sure of the costs, but I suspect one wouldn't have to look at the complete list of these organics (one could leave out some of the chlorinated hydrocarbons that are made as byproduct of the Kraft pulping process for example).
You say,
Hence, my assertion that organics MAY play a role in reef tanks, and that the situation may not be as dire as you claim when you flatly state that we are killing corals.
Yes, the organics may be killing corals and other animals just as much or more so than the metals. So, in fact the situation may more dire.
Incidentally, correct me if I am wrong. You added iron to tanks and got a reduction in sporulation of algae, right? Sporulation of this algae is a normal part of the life cycle, right? So, by adding iron, you effectively altered the life cycle of the algae to prevent reproduction, right? In other words, you poisoned the algae by the addition of the iron, right?
The reason I asked if you had any specific data, to which you showed that you didn't, is that I was wondering if you personally actually had any numerical data to draw on, or if you were simply blowing in the wind.
Perhaps, I should explain that I didn't quite fall off the turnip truck with regard to these chemicals; I have had to use data on them in a number of projects, and some of them, at least, are easily tested for. Incidently, in really high concentrations, they are no longer yellow; they can be purple, black and ochre.
You see, there is a significant body of data regarding the some of these organics in both aquaria and the real world. And there is actually some information about them in coral reef situations, in areas downstream of logging sites.
In specific, in the Pacific NW, and probably elsewhere in the US, some of the major pollutants are pulp mills, and signficant amount of their pollution would be classified as humic acids, and similar kinds of organics. The EPA maintains a list of "Priority Pollutants" to be tested for in pulp mill remediation, etc. Included in this list are a reasonably large number of these types of organics. Data do exist for them with regard to their toxicity toward all sorts of organisms.
Now, are these chemicals the same ones found in our tanks? Maybe, but more likely, maybe not. However, certainly some chemicals characteristic of the various classes of them are. And then, contrarty to your assertions that they can't be examined and must be treated as a "black box," it appears that they can be examined and analysed, at least as first step.
If some of the chemicals on the EPA's priority pollutent list could be considered representative of some of the classes of these organics, then we could test for them in aquaria, and we could look at their effects. Analytical labs, such as the one I used for my metals studies, also routinely examine these pollutants. I am not sure of the costs, but I suspect one wouldn't have to look at the complete list of these organics (one could leave out some of the chlorinated hydrocarbons that are made as byproduct of the Kraft pulping process for example).
You say,
Hence, my assertion that organics MAY play a role in reef tanks, and that the situation may not be as dire as you claim when you flatly state that we are killing corals.
Yes, the organics may be killing corals and other animals just as much or more so than the metals. So, in fact the situation may more dire.
Incidentally, correct me if I am wrong. You added iron to tanks and got a reduction in sporulation of algae, right? Sporulation of this algae is a normal part of the life cycle, right? So, by adding iron, you effectively altered the life cycle of the algae to prevent reproduction, right? In other words, you poisoned the algae by the addition of the iron, right?
andy-hipkiss
New member
Minor (ok major) correction to the Cu result I posted earlier .... having checked with the lab it was 0.211 not 211 ppm 
Duh, I'm used to "." as the decimal separator but here in Belgium they use ",". So "Cu ,211ppm" isn't as I originally posted. Still excitingly high though
Duh, I'm used to "." as the decimal separator but here in Belgium they use ",". So "Cu ,211ppm" isn't as I originally posted. Still excitingly high though
Incidentally, correct me if I am wrong.
Always glad to help out whenever necessary.
Sporulation and other forms of reproduction are a part of the normal life cycle of nearly every organism, yes. They are also often the response to stress. Such stresses are readily observed with the large numbers of organsims that desperately try to reproduce immediately when moved from the ocean to a tank. I've seen many organsims do that in my own tank (I can supply you with genus and species, if that will help you out).
Is that because they are really feeling good about being boxed up? Probably not. More likely it is the well known response to stress.
Likewise, it is also well known that many organisms attempt to flee in whatever way they can when a situation no longer meets their needs (many examples of which are seen even in our tanks). Sporulation is one way of doing so for an otherwise immobile organism.
Incidently, in really high concentrations, they are no longer yellow; they can be purple, black and ochre.
I seem to recall quoting colors to you earlier in this thread in the definition of humic substances. But thanks anyway for the info. If I see any purple or ochre tanks, or if any reefcentral members ask about such a situation, I'll remember this post.
The reason I asked if you had any specific data, to which you showed that you didn't, is that I was wondering if you personally actually had any numerical data to draw on, or if you were simply blowing in the wind.
Since you believe that I cannot carry out scientific experiments, then it would be smarter for me to rely on published works of other scientists, would it not? If I measured it in my tank, would that impress you somehow? What difference would it make? My tank wasn't in your metal study, and is not udergoing any tox testing at the moment, so its seems like unnecessary data. Suffice that other aquaria have been measured.
I have had to use data on them in a number of projects, and some of them, at least, are easily tested for.
Ahhh, I see. In your own words, which one?
Now, are these chemicals the same ones found in our tanks? Maybe, but more likely, maybe not. \
I agree. Spotte has an extensive discussion of the differences between terrestial and marine humic acids, if you want to understand the situation better. Here's a quote :
"Harvey et al (1983) remarked that reports of humus formation and composition in freshwater and terrestial environments are "irrelevant to seawater humus." "
And then, contrarty to your assertions that they can't be examined and must be treated as a "black box," it appears that they can be examined and analysed, at least as first step.
I don't believe that I said black box, so the quotes seem rather inappropriate. I said that they had to be treated in classes. And that is what I provided to you: quantitative tox data on one class (the polyphenolic exudates released from the seaweed Ascophyllum nodosum and then exposed to seawater prior to the test).
It has also been studied in the synthesis lab:
"Harvey et al (1983, 1984) reported that humic substances in seawater are water-soluble, aliphatic organic acids formed by the autoxidative crosslinking of two or more polyunsaturated faty acids...Humus allowed to form in the laboratory under controlled conditions was similar to humic substances that form naturally in seawater"
IN NO CASE, HOWEVER, DOES ANYONE CLAIM THAT A SINGLE SPECIES IS REPRESENTITATIVE. When a single species is not representative, monitoring the concentration of a class of compounds in the presence of many other compounds of similar molecular weight and solubility is very difficult and fraught with uncertainties. To suggest that I have missed the fact that many researchers regularly quatitate individual seawater humic acids and use those numbers to represent the whole class is simply nonsense. If you have any such references to SEAWATER humic substances, please post them.
Yes, the organics may be killing corals and other animals just as much or more so than the metals. So, in fact the situation may more dire.
I quite agree. I said as much earlier in this thread. According to Spotte "So few studies have been done on the toxicity of humus that no general conclusions can be made".
If some of the chemicals on the EPA's priority pollutent list could be considered representative of some of the classes of these organics, then we could test for them in aquaria, and we could look at their effects.
Good start. Most of the known marine toxins aren't man made, so won't be on this list, but it is a good place to begin to see if things like methyl iodide are a problem or not. You'll need a good setup to study such a highly toxic compound, however.
Always glad to help out whenever necessary.
Sporulation and other forms of reproduction are a part of the normal life cycle of nearly every organism, yes. They are also often the response to stress. Such stresses are readily observed with the large numbers of organsims that desperately try to reproduce immediately when moved from the ocean to a tank. I've seen many organsims do that in my own tank (I can supply you with genus and species, if that will help you out).
Is that because they are really feeling good about being boxed up? Probably not. More likely it is the well known response to stress.
Likewise, it is also well known that many organisms attempt to flee in whatever way they can when a situation no longer meets their needs (many examples of which are seen even in our tanks). Sporulation is one way of doing so for an otherwise immobile organism.
Incidently, in really high concentrations, they are no longer yellow; they can be purple, black and ochre.
I seem to recall quoting colors to you earlier in this thread in the definition of humic substances. But thanks anyway for the info. If I see any purple or ochre tanks, or if any reefcentral members ask about such a situation, I'll remember this post.
The reason I asked if you had any specific data, to which you showed that you didn't, is that I was wondering if you personally actually had any numerical data to draw on, or if you were simply blowing in the wind.
Since you believe that I cannot carry out scientific experiments, then it would be smarter for me to rely on published works of other scientists, would it not? If I measured it in my tank, would that impress you somehow? What difference would it make? My tank wasn't in your metal study, and is not udergoing any tox testing at the moment, so its seems like unnecessary data. Suffice that other aquaria have been measured.
I have had to use data on them in a number of projects, and some of them, at least, are easily tested for.
Ahhh, I see. In your own words, which one?
Now, are these chemicals the same ones found in our tanks? Maybe, but more likely, maybe not. \
I agree. Spotte has an extensive discussion of the differences between terrestial and marine humic acids, if you want to understand the situation better. Here's a quote :
"Harvey et al (1983) remarked that reports of humus formation and composition in freshwater and terrestial environments are "irrelevant to seawater humus." "
And then, contrarty to your assertions that they can't be examined and must be treated as a "black box," it appears that they can be examined and analysed, at least as first step.
I don't believe that I said black box, so the quotes seem rather inappropriate. I said that they had to be treated in classes. And that is what I provided to you: quantitative tox data on one class (the polyphenolic exudates released from the seaweed Ascophyllum nodosum and then exposed to seawater prior to the test).
It has also been studied in the synthesis lab:
"Harvey et al (1983, 1984) reported that humic substances in seawater are water-soluble, aliphatic organic acids formed by the autoxidative crosslinking of two or more polyunsaturated faty acids...Humus allowed to form in the laboratory under controlled conditions was similar to humic substances that form naturally in seawater"
IN NO CASE, HOWEVER, DOES ANYONE CLAIM THAT A SINGLE SPECIES IS REPRESENTITATIVE. When a single species is not representative, monitoring the concentration of a class of compounds in the presence of many other compounds of similar molecular weight and solubility is very difficult and fraught with uncertainties. To suggest that I have missed the fact that many researchers regularly quatitate individual seawater humic acids and use those numbers to represent the whole class is simply nonsense. If you have any such references to SEAWATER humic substances, please post them.
Yes, the organics may be killing corals and other animals just as much or more so than the metals. So, in fact the situation may more dire.
I quite agree. I said as much earlier in this thread. According to Spotte "So few studies have been done on the toxicity of humus that no general conclusions can be made".
If some of the chemicals on the EPA's priority pollutent list could be considered representative of some of the classes of these organics, then we could test for them in aquaria, and we could look at their effects.
Good start. Most of the known marine toxins aren't man made, so won't be on this list, but it is a good place to begin to see if things like methyl iodide are a problem or not. You'll need a good setup to study such a highly toxic compound, however.
So, by adding iron, you effectively altered the life cycle of the algae to prevent reproduction, right? In other words, you poisoned the algae by the addition of the iron, right?
One other comment on this. In my iron paper there is a picture of one of my refugia taken about 1 month ago. It shows a bit of Caulerpa racemosa growing around the edges.
Today I had to go in and remove about 2 gallons of the Caulerpa. It had grown to solid packing across the entire surface of the water, and through most of the water column down to the bottom (about 8 inches) preventing light from getting to the corals underneath.
That doesn't sound like poisoned macroalgae barely struggling to survive against a toxic onslaught of 800 million times the normal iron concentration every day. It sounds like a very active export mechanim for nitrogen and phosphorus (and potentially other things
). Would that have happened without the iron additions? Maybe. I don't post it to claim the iron is responsible. But it did happen in the presence of the iron, so the iron is clearly not causing a substantial problem with using macroalgae as an export mechanism.
One other comment on this. In my iron paper there is a picture of one of my refugia taken about 1 month ago. It shows a bit of Caulerpa racemosa growing around the edges.
Today I had to go in and remove about 2 gallons of the Caulerpa. It had grown to solid packing across the entire surface of the water, and through most of the water column down to the bottom (about 8 inches) preventing light from getting to the corals underneath.
That doesn't sound like poisoned macroalgae barely struggling to survive against a toxic onslaught of 800 million times the normal iron concentration every day. It sounds like a very active export mechanim for nitrogen and phosphorus (and potentially other things
). Would that have happened without the iron additions? Maybe. I don't post it to claim the iron is responsible. But it did happen in the presence of the iron, so the iron is clearly not causing a substantial problem with using macroalgae as an export mechanism.
Presently, the result of this metals overabundance is unclear. I think it is cause for concern. Randy doesn't. He likes 'em.
The only one that I dose, and the only one that I recommend others dose is iron. That's the one that I like.:love2:
Is there any evidence whatsoever that there is an overabundance of iron in any operating reef tank?
If so, please post it.
Otherwise, I'd appreciate your not generalizing your concerns about certain metals that you measured to others that you were unable to detect.
The only one that I dose, and the only one that I recommend others dose is iron. That's the one that I like.:love2:
Is there any evidence whatsoever that there is an overabundance of iron in any operating reef tank?
If so, please post it.
Otherwise, I'd appreciate your not generalizing your concerns about certain metals that you measured to others that you were unable to detect.
You truly DO miss the forest for the trees, don't you. I am not saying perfecting salt mixes would be the end all. Just the first step. Contamination comes from many sources, salt mixes are just the first thing to fix.
But Ron, it doesn't help even a tiny bit. Why wage war against something that won't help even a TINY bit?
In your study, you write:
"Sample GD was from a tank that uses NSW as a medium, and as shown in the dendrograms, no matter how the data are manipulated, that particular sample is never very similar to NSW. "
Let's examine tank GD.
It is the highest or second highest for:
arsenic, boron, cobalt, copper, nickel, and vanadium
A list that incorporates most of your most-mentioned metal toxins.
This data suuggests that lowering the metals in the salt mixes will do NOTHING to help.
Do you have some other data that suggests that it will actually help something? Even a little bit?
Were there any other tanks in your study that claimed to use NSW? Which ones, so we can look at the metal concentrations in them as well.
But Ron, it doesn't help even a tiny bit. Why wage war against something that won't help even a TINY bit?
In your study, you write:
"Sample GD was from a tank that uses NSW as a medium, and as shown in the dendrograms, no matter how the data are manipulated, that particular sample is never very similar to NSW. "
Let's examine tank GD.
It is the highest or second highest for:
arsenic, boron, cobalt, copper, nickel, and vanadium
A list that incorporates most of your most-mentioned metal toxins.
This data suuggests that lowering the metals in the salt mixes will do NOTHING to help.
Do you have some other data that suggests that it will actually help something? Even a little bit?
Were there any other tanks in your study that claimed to use NSW? Which ones, so we can look at the metal concentrations in them as well.
Randy,
[That doesn't sound like poisoned macroalgae barely struggling to survive against a toxic onslaught of 800 million times the normal iron concentration every day. It sounds like a very active export mechanim for nitrogen and phosphorus (and potentially other things
). No, it simply sounds actually like you are exporting enough algae to keep the algae below the size necessary for reproduction. However, if the iron does shut off the reproductive process, that is still a poison, and vegetative growth can still occur.
The point being that poisons don't have to kill, simply altering the target metabolism in a way that destroys reproductive fitness also works.
Is that because they are really feeling good about being boxed up? Probably not. More likely it is the well known response to stress.
For the alga, it is more likely and simply a size thing. Although the release of the spores is rapid, the interal cell division that leads to it generally takes several days. This is not a process that occurs in the algae in response to immediate stress, unless the species was already primed to go.
If you have had other algae and animals respond to placement in your tanks by spawning, I would say that something is pretty drastically wrong. From my most recent article, I would suggest that they are being put into a situation where the toxic chemical load is far beyond their capabilty to compensate for, and that causes the spawning.
IN NO CASE, HOWEVER, DOES ANYONE CLAIM THAT A SINGLE SPECIES IS REPRESENTITATIVE. When a single species is not representative, monitoring the concentration of a class of compounds in the presence of many other compounds of similar molecular weight and solubility is very difficult and fraught with uncertainties.
Oh, I agree. However, it is a start. One war at a time...
To suggest that I have missed the fact that many researchers regularly quatitate individual seawater humic acids and use those numbers to represent the whole class is simply nonsense. If you have any such references to SEAWATER humic substances, please post them.
No, sir, it is not nonsense to suggest that you have missed the fact that researchers have regularly sampled these substances. You appear to be using only one reference, Spotte, and the references therein. Nothing more recent that the mid-1980's. A lot has happened since then.
Much of this is in the so-called gray literature, however, there is a lot, I think, in Marine Pollution Bulletin. I have not searched the literature recently for these data specifically, as I haven't been interested in addressing any problems revolving around organics in our systems. And, from where I am at, I really can't get into the data bases I need either - my local university can barely keep the library doors open, let alone subscribe to marine journals. It is also likely that it will be several months before I can make a trip to Seattle to get to the UW library which has these data. So... if you want some of this, you're going to find it on your own.
I will try to dig out my lists of the priority pollutents over the next few days (these are in boxes in my stacks of these publications in my garage) and if I can find a complete one, I will send it to you. Until then, if you want, you can do a search under "EPA priority pollutents" and you may find them. In case they vary from EPA region to region, most of my work was in Region 10.
I was going to suggest that we might be able to work up a collaborative project on this, one that might well result in publication in the professional literature as well as in the hobbyist press, but in light of your contentious response, I think such a project would have little chance of success.
This data suuggests that lowering the metals in the salt mixes will do NOTHING to help.
And you miss the point, again.
The poison levels are cumulative. Most of them initially come in ultrahigh doese with the water in most tanks. They are replenished with the water.
If we can remove them from the water the levels will be lower. Maybe well below toxic levels.
In the particular tank in question, they are undoubtedly coming in with foods, and maybe other additives. Accumulation continues through time as export of the damnable substances is inefficient. That they accumulate, simply means export is not occurring.
Dear Ron, Dear Sir and others,
Humic Acids (HA):
Based on UV-VIS spectra which I had recorded of several aquaria I estimate the HA content to be approx. 0.5 - 10 ppm. It can be much higher but most probably not lower. I had to make some estimates regarding molecular extinction coefficient and have used a value which very likely undeestimates the actual HA concentration. I have also taken a low molecular weight which also can lead to an underestimation.
I am also including a few cuttings:
C-Functional Group Chemistry of Humic Substances and
Their Spatial Variation in Soils
S. C. B. Myneni 1 , T. A. Warwick 2 , G. A. Martinez 3 , G. Meigs 2
1 Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
2 Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
3 Agriculture Experiment Station, University of Puerto Rico, San Juan, PR 00936-4984, USA
Organic molecules derived from biological processes and the biochemical alteration of plant and
animal residue are common in soils and natural aquatic systems and their concentration ranges
from <1 ppm to as high as 4x10 5 ppm. Their composition varies widely with location and origin
(e.g. soil, marine), and consists of small chain molecules (e.g. acetate, citrate), organic
macromolecules (e.g. proteins), and polyfunctional humic substances (HS)1 . Of these, humic
substances exist at high concentrations, and are stable to biochemical alteration with long
lifetime. In addition, HS can form strong complexes with both inorganic and organic
contaminants and mineral surfaces, and thus play a major role in geochemical processes 2 . At least
for a century, research has been focused on understanding the HS functional group chemistry and
the macromolecular structure - the properties of HS that control their behavior in the
environment.
The following is from an online aquariumfrontiers article by Randy:
Organics
The nature of organic molecules is certainly the most complicated aspect of seawater chemistry. Organics comprise about 2 ppm of seawater. Of this 2 ppm, the majority is in the form of dissolved organic carbon (DOC). DOC includes all fully dissolved organic compounds and any particulates that are small enough to pass through a 0.45-micron (Ã"šÃ‚µm) glass fiber filter. Strictly speaking then, it is not all fully dissolved. Any organic particles greater than 0.45 Ã"šÃ‚µm are called particulate organic carbon (POC). The POC is about a factor of 10 lower in concentration than DOC and is composed of living and dead organisms, as well as assemblies of organic molecules.
DOC is an incredibly complicated mixture of molecules that represents billions of years of biological waste products from uncounted numbers of different organisms, combined with reactions catalyzed by light, heat, inorganic catalysts (metals), biological processes, and many other factors. It includes carbohydrates (20 to 35 percent of the total), humic substances (10 to 30 percent of the total), amino acids and proteins (2 to 3 percent), hydrocarbons (less than 1 percent), carboxylic acids (1 percent) and steroids (trace).
There is also a great deal of uncharacterized organic material. In fact, the study of seawater organics is an active area of research. Additionally, the summation of all dissolved organics in the ocean is a pool of carbon larger than carbon dioxide in the atmosphere, so it cannot be ignored by those looking at the planetary carbon cycle. In addition to carbon, these organics contain significant amounts of oxygen, nitrogen, phosphorus, and sulfur.
It is probably also safe to say that most, if not all, closed marine systems have higher organic levels than the ocean, although hard numbers are difficult to come by. The desire to reduce these organic levels is one of the reasons for the popularity of skimmers with marine aquaria.
Anothe one:
........Humic and fulvic acids have strong affinities for most metals and therefore influence metal mobilization and bioavailability in the environment. [5,1]. Characterizing these complex multivariate interactions is fundamental to the prediction and control of metal speciation [6,1,5].
The nature of humic-metal complexation is neither understood nor agreed upon [1,6]. However, because HFAs have numerous binding sites with a continuum of binding strengths it is agreed that they can not be treated as simple, isolated molecules [7]. Because of the complexity of humic-metal interactions, their stability constants and complexation capacities depend on pH, ionic strength, metal concentration, presence of interferents, and the nature of the particular HFA [7, 8]. .........
and others,Humic Acids (HA):
Based on UV-VIS spectra which I had recorded of several aquaria I estimate the HA content to be approx. 0.5 - 10 ppm. It can be much higher but most probably not lower. I had to make some estimates regarding molecular extinction coefficient and have used a value which very likely undeestimates the actual HA concentration. I have also taken a low molecular weight which also can lead to an underestimation.
I am also including a few cuttings:
C-Functional Group Chemistry of Humic Substances and
Their Spatial Variation in Soils
S. C. B. Myneni 1 , T. A. Warwick 2 , G. A. Martinez 3 , G. Meigs 2
1 Earth Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
2 Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
3 Agriculture Experiment Station, University of Puerto Rico, San Juan, PR 00936-4984, USA
Organic molecules derived from biological processes and the biochemical alteration of plant and
animal residue are common in soils and natural aquatic systems and their concentration ranges
from <1 ppm to as high as 4x10 5 ppm. Their composition varies widely with location and origin
(e.g. soil, marine), and consists of small chain molecules (e.g. acetate, citrate), organic
macromolecules (e.g. proteins), and polyfunctional humic substances (HS)1 . Of these, humic
substances exist at high concentrations, and are stable to biochemical alteration with long
lifetime. In addition, HS can form strong complexes with both inorganic and organic
contaminants and mineral surfaces, and thus play a major role in geochemical processes 2 . At least
for a century, research has been focused on understanding the HS functional group chemistry and
the macromolecular structure - the properties of HS that control their behavior in the
environment.
The following is from an online aquariumfrontiers article by Randy:
Organics
The nature of organic molecules is certainly the most complicated aspect of seawater chemistry. Organics comprise about 2 ppm of seawater. Of this 2 ppm, the majority is in the form of dissolved organic carbon (DOC). DOC includes all fully dissolved organic compounds and any particulates that are small enough to pass through a 0.45-micron (Ã"šÃ‚µm) glass fiber filter. Strictly speaking then, it is not all fully dissolved. Any organic particles greater than 0.45 Ã"šÃ‚µm are called particulate organic carbon (POC). The POC is about a factor of 10 lower in concentration than DOC and is composed of living and dead organisms, as well as assemblies of organic molecules.
DOC is an incredibly complicated mixture of molecules that represents billions of years of biological waste products from uncounted numbers of different organisms, combined with reactions catalyzed by light, heat, inorganic catalysts (metals), biological processes, and many other factors. It includes carbohydrates (20 to 35 percent of the total), humic substances (10 to 30 percent of the total), amino acids and proteins (2 to 3 percent), hydrocarbons (less than 1 percent), carboxylic acids (1 percent) and steroids (trace).
There is also a great deal of uncharacterized organic material. In fact, the study of seawater organics is an active area of research. Additionally, the summation of all dissolved organics in the ocean is a pool of carbon larger than carbon dioxide in the atmosphere, so it cannot be ignored by those looking at the planetary carbon cycle. In addition to carbon, these organics contain significant amounts of oxygen, nitrogen, phosphorus, and sulfur.
It is probably also safe to say that most, if not all, closed marine systems have higher organic levels than the ocean, although hard numbers are difficult to come by. The desire to reduce these organic levels is one of the reasons for the popularity of skimmers with marine aquaria.
Anothe one:
........Humic and fulvic acids have strong affinities for most metals and therefore influence metal mobilization and bioavailability in the environment. [5,1]. Characterizing these complex multivariate interactions is fundamental to the prediction and control of metal speciation [6,1,5].
The nature of humic-metal complexation is neither understood nor agreed upon [1,6]. However, because HFAs have numerous binding sites with a continuum of binding strengths it is agreed that they can not be treated as simple, isolated molecules [7]. Because of the complexity of humic-metal interactions, their stability constants and complexation capacities depend on pH, ionic strength, metal concentration, presence of interferents, and the nature of the particular HFA [7, 8]. .........
If you have had other algae and animals respond to placement in your tanks by spawning, I would say that something is pretty drastically wrong.
Absolutely, they responded to stress by trying to reproduce. I think it is a reasonable hypothesis that Caulerpa racemosa responds the same way when given a shortage of iron, but as I noted in my article, such a hypothesis requires much further testing, and is not something that I believe to be more than a working hypothesis.
I actually wasn't referring to algae at all in my tank, but spawning of bivalves, limpets, urchins, and hermit crabs.
Absolutely, they responded to stress by trying to reproduce. I think it is a reasonable hypothesis that Caulerpa racemosa responds the same way when given a shortage of iron, but as I noted in my article, such a hypothesis requires much further testing, and is not something that I believe to be more than a working hypothesis.
I actually wasn't referring to algae at all in my tank, but spawning of bivalves, limpets, urchins, and hermit crabs.
Based on UV-VIS spectra which I had recorded of several aquaria I estimate the HA content to be approx. 0.5 - 10 ppm.
Come on, Habib, since I haven't measured it personally in my tank, it can't be known.
For what it's worth, that puts it into the potential toxic range (0.32 mg/L for the LC50 with plaice larvae) IF what you measured has the same toxicity as that measured by Sieberth and Johnson. Of course, it likely does not because that toxic fraction is only a part of the total, and the toxicity is lower after complete humification.
Come on, Habib, since I haven't measured it personally in my tank, it can't be known.
For what it's worth, that puts it into the potential toxic range (0.32 mg/L for the LC50 with plaice larvae) IF what you measured has the same toxicity as that measured by Sieberth and Johnson. Of course, it likely does not because that toxic fraction is only a part of the total, and the toxicity is lower after complete humification.
No, it simply sounds actually like you are exporting enough algae to keep the algae below the size necessary for reproduction.
You may have hit on something here, Ron. Adding iron may make it grow robustly enough that people do need to prune it, and the pruning is important in preventing the sexual phase.
Many people have suggested that pruning helps. Then in the absence of added iron, growth is slow enough that people don't need or bother to prune, and the algae can proceed to an unwanted sexual phase.
Thanks for the suggestion. If I put it into a followup article, I'll be sure and credit you with the idea
You may have hit on something here, Ron. Adding iron may make it grow robustly enough that people do need to prune it, and the pruning is important in preventing the sexual phase.
Many people have suggested that pruning helps. Then in the absence of added iron, growth is slow enough that people don't need or bother to prune, and the algae can proceed to an unwanted sexual phase.
Thanks for the suggestion. If I put it into a followup article, I'll be sure and credit you with the idea
I was going to suggest that we might be able to work up a collaborative project on this, one that might well result in publication in the professional literature as well as in the hobbyist press, but in light of your contentious response, I think such a project would have little chance of success.
Hmmm, proposed that way, I'd have to agree
Hmmm, proposed that way, I'd have to agree
