Sixty’s Understanding of Nutrient Ratios

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@Randy Holmes-Farley would you be willing in Removing the words “of Redfield” from the title of the thread and move this thread to a place in the forum that could be more suitable for the evolution of the discussion?
I realised I’ve made a mistake in having “Redfield” in the title I tough in messaging a mod to remove it but felt out of place in doing so.

the intension is to discuss the importance of Ratios effects in Nutrient limitations scenarios not necessarily around just one, the theoretical formula is based on the assumption that most microbes in a system utilises nutrient in a C N P ratio and as I’ve expressed several times during the thread that ratio may not be Redfield although I believe there will be a ratio that is unknown. I’d like to carry on having a civil productive discussion on the subject if possible and understand that we may not be in the right place to do so.
 
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I changed the title (seem good?). If you want it moved to a different subforum, which one?
Yes that’s perfect, thank you, i would like it for you to decide if possible, you may know better in witch sub forum would be suitable for this type of discussion.
 

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Yes that’s perfect, thank you, i would like it for you to decide if possible, you may know better in witch sub forum would be suitable for this type of discussion.

In general, I think either the forum its in or the chemistry forum. Both have folks interested in this sort of topic.

The Reef discussion forum will have more folks wanting to use a method that might be helpful to them, and the chem forum may have more folks interested in the rationale for the method.
 
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In general, I think either the forum its in or the chemistry forum. Both have folks interested in this sort of topic.

The Reef discussion forum will have more folks wanting to use a method that might be helpful to them, and the chem forum may have more folks interested in the rationale for the method.
Could we move to the chemistry forum? I feel that discussion the rationale is more important than application, if you ok with that.
 
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Your choice. :)
Let’s do it, It would be good to have great minds scrutinising the theory

with the theory being, that it may well be possible to find the abundance or limitations of C N P by interpreting the residual unused nutrient of No3 and Po4 and use the information to reduce or eliminate common aquarists problems.
 
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Maybe this thread will finally put to rest the use of the "redfield ratio" in this hobby? Probably not, but it would be a good start. I'm not sure who started it's use or reference in relation to our tanks, but it's completely and utterly useless to what we're trying to achieve. I think we have to use "ranges" rather than "ratios" in regards to C -N-P uptake. If there was a magic ratio, then we would all be using it and be successful, but that's not the case. Instead, we should focus of PO4 levels and ranges of NO3 in relation to PO4. Each tank will be limited by one or the other, sometimes both in certain conditions. The other thing to factor in is not all corals have the same requirements of C-N-P, so those ratios will always be different depending on genera or species. But the most important thing here is: Redfield ratio is a complete waste of time and should be banned from our hobby. (I'm joking of course, but you kinda get the point) Alright, back to the intelligent conversation.
 
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Maybe this thread will finally put to rest the use of the "redfield ratio" in this hobby? Probably not, but it would be a good start. I'm not sure who started it's use or reference in relation to our tanks, but it's completely and utterly useless to what we're trying to achieve. I think we have to use "ranges" rather than "ratios" in regards to C -N-P uptake. If there was a magic ratio, then we would all be using it and be successful, but that's not the case. Instead, we should focus of PO4 levels and ranges of NO3 in relation to PO4. Each tank will be limited by one or the other, sometimes both in certain conditions. The other thing to factor in is not all corals have the same requirements of C-N-P, so those ratios will always be different depending on genera or species. But the most important thing here is: Redfield ratio is a complete waste of time and should be banned from our hobby. (I'm joking of course, but you kinda get the point) Alright, back to the intelligent conversation.
I completely understand your point of view, although I must disagree, compared to the other parameters (ex. Ca Alk Mg) I believe we don’t interpret the residual unused concentration of po4 and no3 to its full potential. You are also right in saying that different coral will have different needs and that redfield is useless because we not growing phytoplankton in our tank. I’m not using redfield to try and grow phytoplankton, I’m using redfield as a reference as it’s the closest known number to sea water and marine organic detritus and most likely the number closest to the average usage/Needs of nutrients of all microbes living in our systems, am using redfield as a guide for water stability knowledge that should reflect on parameters stability as a conclusion I’m using redfield as a guide line to interpret the nutrient needs of microbes in a salt water aquarium. If the residual unused concentration of Calcium in a reef where to lower or increase most would do changes to the amount of Calcium added to the tank to bring stability back and assume that the change occurred because the system need more or less the amount of that element to stay stable. The same can happen With knowledge on interpretation of residual unused concentration of no3 and po4 and using the right interpretation we can assume if our tank needs more or less nutrients to stay stable.
In addition not being able to interpret the changes in needs of nutrients can be directly connected with most common issues that we face today as saltwater aquarists. Ex. Cyanobacteria, dinoflagellates and undesirable algae outbreaks that most of the time occurs wend parameters have lost they’re stability allowing undesirable pests to overrun a system.
 
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I still wouldn't use Redfield as a baseline, as it only represents one facet of marine life, which doesn't exist in our tanks unless we dose it (live phytoplankton) and is consumed rapidly and doesn't proliferate for any length of time. The issues with dinos and other nasty guys are a result of using dry rock and the lack of biodiversity in bacteria. You're better off targeting a range of PO4 and then targeting a range of NO3 according to your system's needs/uptake. There's no magic number or ratio here. Redfield is an absolute waste of time and shouldn't be a consideration concerning our tank's needs. I've seen successful tanks range from 100:1, 50:1 10:1 or below. Again, I would urge you to completely disregard Redfield altogether. I think a more useful tool or route to understanding our tank's ratios or ranges would be to sample the microbiome and compare its ability to "process" N & P. Then maybe we can see which bacteria strains are the ones that keep balance in our tanks? Latching onto Redfield in this hobby does us a disservice, as it distracts from the actual science in our tanks. I definitely think it's worth a deep dive into understanding our tanks biological processes, but we shouldn't use Redfield as a reference point. Why not use the ratios that I mentioned earlier from those successful tanks? Because they're completely different from each other, in every regard.
 
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I still wouldn't use Redfield as a baseline, as it only represents one facet of marine life, which doesn't exist in our tanks unless we dose it (live phytoplankton) and is consumed rapidly and doesn't proliferate for any length of time. The issues with dinos and other nasty guys are a result of using dry rock and the lack of biodiversity in bacteria. You're better off targeting a range of PO4 and then targeting a range of NO3 according to your system's needs/uptake. There's no magic number or ratio here. Redfield is an absolute waste of time and shouldn't be a consideration concerning our tank's needs. I've seen successful tanks range from 100:1, 50:1 10:1 or below. Again, I would urge you to completely disregard Redfield altogether. I think a more useful tool or route to understanding our tank's ratios or ranges would be to sample the microbiome and compare its ability to "process" N & P. Then maybe we can see which bacteria strains are the ones that keep balance in our tanks? Latching onto Redfield in this hobby does us a disservice, as it distracts from the actual science in our tanks. I definitely think it's worth a deep dive into understanding our tanks biological processes, but we shouldn't use Redfield as a reference point. Why not use the ratios that I mentioned earlier from those successful tanks? Because they're completely different from each other, in every regard.
I feel that am experiencing some sort of twilight zone, how can we make a useful ratio between po4 and no3? Why does everyone believe that there’s a ratio here


What’s the best ratio between Magnesium and Ph or Dkh and po4 or no3 and calcium

can a useful ratio between different parameters be made :)
 
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I would target ranges, not ratios. That seems to be a more realistic goal for what we're trying to achieve. Ratios are fixed, but our tanks are in a constant flux compared to the ocean's, so a range seems far more attainable. Plus, we're not dosing equal parts of alk/ca/mag, we dose according to their uptake/consumption, which isn't fixed either.
 

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I feel that am experiencing some sort of twilight zone, how can we make a useful ratio between po4 and no3? Why does everyone believe that there’s a ratio here


What’s the best ratio between Magnesium and Ph or Dkh and po4 or no3 and calcium

can a useful ratio between different parameters be made :)

I'm not sure what you are asking.

Scientists who discuss the Redfield ratio are looking at one of two things:

1. The C/N/P ratio in phytoplankton
2. The C/N/P ratio of available elements in seawater

Those same ratios do not apply to some of the processes in reef tanks, which is why many tanks get elevated N or P and not the other.

If someone wants to use these ratios (or any other ratio they choose) to set target values for a reef tank, then that is a new endeavor not addressed by any scientific literature, at least not if the absolute levels do not mimic the ocean (which few reefers seem to want to do currently).

Thus, any desire to use ratio in a reef tank needs, IMO, to meet three critical criteria:

1. The ratio is found to be useful in some demonstrated context
2. It is shown that the ratio is useful across a wide range of absolute values that reefers generally encounter
3. That the ratio has some merit above simply targeting every individual element at a desirable absolute level

I do not think these criteria have been met for either the Redfield ratio or any other ratio to make them useful for setting target levels in a reef tank.
 
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Plus, we're not dosing equal parts of alk/ca/mag, we dose according to their uptake/consumption, which isn't fixed either.

As we are not feeding the same amount of food neither that contain Carbon Nitrogen and Phosphorus we fix our nutrient levels according what we feed or add to the tank. And they are manipulated the same way as the other parameters although they need three elements instead of just one making more complicated to understand.

we need to treat nutrients as we threat all our other parameters to understand the bigger picture behind.
 
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I'm not sure what you are asking.

Scientists who discuss the Redfield ratio are looking at one of two things:

1. The C/N/P ratio in phytoplankton
2. The C/N/P ratio of available elements in seawater
the C/N/P ratio of available in seawater

Those same ratios do not apply to some of the processes in reef tanks, which is why many tanks get elevated N or P and not the other.
I believe we can adjust the input of elements to manipulate No3 and Po4 and use the theoretical formula to create a map that will allow anyone to determine the outcome of change’s to a system before they are implemented. At this point and time only a few roads are known from that map, and wend the New map aligns with the known roads it should help in validation of the formula



If someone wants to use these ratios (or any other ratio they choose) to set target values for a reef tank, then that is a new endeavor not addressed by any scientific literature, at least not if the absolute levels do not mimic the ocean (which few reefers seem to want to do currently).
It will be written somewhere, it would be hard to think that it is not, the goal is not to replicate the ocean absolute levels the end goal is to achieve stability and manipulate the nutrients if stability is lost at some point.
Thus, any desire to use ratio in a reef tank needs, IMO, to meet three critical criteria:

1. The ratio is found to be useful in some demonstrated context
I haven’t had a chance as no one yet understood that there is no ratio between No3 and Po4, they just residual unused concentration of nutrients and their absolute value is not relatively important as long as they on a range that is not toxic for the tank inhabitants, the changes in build up or reduced concentration are important to identify movements in the abundance or limitation of nutrients available in a tank. The real ratio is in the chemical content of food and other nutrients added to the tank. We can’t discuss the theory until there is an agreement on we’re the ratio is found, if a connection keeps being made between no3 and po4 we can’t proceed to a more productive and elaborate discussion.
the chain of events that uses the ratio is happening on a constant motion and can’t be measured in absolute numbers the chain of events that uses the ratio is not found in the “left over nutrient” or residual unused nutrient.
2. It is shown that the ratio is useful across a wide range of absolute values that reefers generally encounter
Once step one is understood (knowing we’re the ratio is) and step two ( interpretation of change of build up or reduction of residual unused nutrient) a more comprehensive discussion can happen to evaluate the meaning of the different results for different problems. (Once again we haven’t crossed step 1 this far in the discussion)

3. That the ratio has some merit above simply targeting every individual element at a desirable absolute level
the theoretical formula should allow to make identifications on what’s limited allowing for corrections and stabilise parameters if something happens that makes them starting to build up or reduce. Again we haven’t explore the theory as we still discussing we’re the nutrient ratio is unfortunately.

I do not think these criteria have been met for either the Redfield ratio or any other ratio to make them useful for setting target levels in a reef tank.
 
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