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@Randy Holmes-Farley just a last attempt at explaining myself a little better.
if a tank is experiencing a high residual nitrate let’s say 30ppm and a high residual phosphates let’s say 0.2 ppm
by increasing the availability of organic carbon, theoretically we could bring both residual values to 5ppm nitrate and 0.1 ppm residual phosphates (more or less)
Now in theory assuming that the above is more or less correct could the following be possible?
a tank is experiencing high residual phosphates for example, 5ppm residual nitrate and 0.2 ppm residual phosphates.
Could we increase artificially the residual nitrates to 30ppm and increase the availability of organic carbon in order to reduce the residual phosphates down to 0.1 ppm again?
a tank start to show build up in residual nitrates with 0 residual phosphates wile carbon dosing.
could we theoretically artificially increase the availability of phosphates to reduce residual nitrates?
A tank is showing 0 ppm residual nitrates and 0 ppm residual phosphates
could we artificially increase the availability of nitrates and phosphates to increase the residual of nitrates and phosphates.
it’s a boring exercise although it may be helpful with the idea that all 3 nutrients have a connection and can be manipulated to achieve different results.
The thing that am not being able to explain correctly is the difference between availability and residual they both have completely different meaning wend referring to nutrients.
@Dan_P this could also be helpful to understand the information I have posted earlier.
FYI, any time I refer to nutrient levels, that means levels in the water by analysis. You are referring to that as residual nutrients. Same thing.
The numbers are just random number to illustrate that the process is possible to do. And it’s only possible if C is added agaiExcercise #1.
Certainly, adding organic carbon will reduce N and have a small effect on P. If one of them depletes before the other, and you want to use organic carbon dosing to drive the higher one down, dosing the lower one can be useful. That's a standard procedure.
BUT, it is not correct, IMO, to suggest that in a reef tank at 5ppm nitrate and 0.2 ppm phosphates that adding mroe nitrate to 30 ppm will lower P. That tank is not likely nitrate limited at 5 ppm, so adding more has no substantial effect.
no, you answered as I thought you would as this is just standard procedure.Exercise #2.
Yes, in a tank with undetectable N or P, adding the undetectable one can boost consumption of the other since many photosynthetic organisms may be N or P limited by the undetectable one. Again, this is a standard recommendation: dose the undetectable one.
Can we boost undetectable nutrients by dosing them? Certainly. Did you have something different in mind?
no, you just confirmed the probable out comes to nutrient wile carbon dosing, I’ve tried, I can’t find one that wouldn’t match with it. Hoped that someone could find a situation involving nutrients that the formula couldn’t come up with a logic explanationI don’t recall saying or thinking that any particular formula applies to carbon dosing or nutrient dosing. I’m actually quite confident it would not in most cases since there are a variety of different ways C, N, and P can all be used in different ratios.
For example, to raise P by dosing or feeding often takes far more than one predicts because a lot of what was dosed ends up binding to calcium carbonate surfaces.
if the food supplement has a balanced C N P ratio,would be difficult to lowe P that way, and a food supplement with less P to C and N ratio could aid this particular situationLikewise, when trying to deplete it, it may take a long time to get it down due to phosphate desorbing from those surfaces.
Those processes have no impact on or by DOC or nitrate.
Spent a long time trying to understand what was actually done, it’s interesting what he done.I don’t think I drew a conclusion about carbon in any food, but others may have done so.
The extreme phosphate binding to bare rock was demonstrated by JDA and is unrelated to bacteria or C or N.
Bare rock can take up tens of ppm phosphate.
Spent a long time trying to understand what was actually done, it’s interesting what he done.
to my understanding of the thread is that water in a tank was brought up to a certain ppb and then a reactor containing aragonite gravel was plumed to it to try and quantity a measurement of absorption.
Is that correct?
I didn’t see a control tank to check if the tank itself could be absorbing phosphates.
Or if the powder wasn’t setting in the tank.
To many variables in the test to be conclusive imo
although even if correct it wouldn’t change anything in my theory.
Out of curiosity what was the determination of a trigger point for releasing of phosphates by aragonite?He added more than 50 ppm based on knowing what was added before levels got to around 0.15 ppm in the water. No control tank is needed for that type of experiment.
such binding is established in the scientific literature.
Out of curiosity what was the determination of a trigger point for releasing of phosphates by aragonite?
It doesn’t make any sense to me, you just mentioned that in the test the phosphates were reduced by 49.85 ppm, meaning that the rock absorbed a large amount of phosphates, if something binds to something it needs a trigger point to unbind.There no trigger point for this sort of binding. More in the water means more on the surface, and less in the water means less on the surface. That means the surface phosphate releases and additions buffers both up and down changes in phosphate.
It doesn’t make any sense to me, you just mentioned that in the test the phosphates were reduced by 49.85 ppm, meaning that the rock absorbed a large amount of phosphates, if something binds to something it needs a trigger point to unbind.
min this comment it seems that you mean that is being diluted in the surface area of the rock.
Thank you for the more elaborated explanation, I still can’t see it affecting the discussion, because as you said there is a balance and if it were to reach zero on the water it most likely mean that there would be zero stored in the rock surfaces to.I think you do not understand the process of binding to surfaces.
It is a rapid on off equilibrium happening all the time, not a one way street. There is an equilibrium that exists between the phosphate in the water and the phosphate on the solid surface. The more in the water, the more on the surface. As soon as you add mroe to the water, more binds to the surface. As soon as you take some out of the water, some comas off the surface.
This is nothing unusual. It is a very well studied phenomenon for many types of materials binding to many types of surfaces, but in this case, it has also been studied by one of the leading chemical oceanographers in the world (Frank Millero):
Adsorption of Phosphate on Calcium Carbonate
Frank J. Millero, University of Miami/RSMAS, Miami, FL; Jia-Zhong Zhang, NOAA/AOML/OCD, Miami, FL
Phosphate, as a limiting nutrient, is critical to the onset and sustainment of phytoplankton blooms in Florida Bay. The adsorption of phosphate on suspended biogenic calcium carbonates (aragonite and calcite) is believed to be an important mechanism for removal of phosphate in the natural waters. Understanding the transportation and transformation of phosphate in the environment is important to the water quality of Florida Bay.
Laboratory experiments on phosphate adsorption show that the adsorption of phosphate on calcite and aragonite is a fast process. Generally it takes about 5 minutes for the adsorbed phosphate concentration to reach a constant value. Aragonite offers more active surface and more active adsorptive sites than calcite. The capacity of adsorption on the aragonite is about 20 times higher than calcite based on moles of phosphate adsorpted on per gram of particle. Adsorption isotherms have been constructed based on the equilibrium experiments of phosphate adsorption on aragonite at pH of 8.0 in seawater over salinity range of 5-35 and temperature range of 5 - 45 oC at initial phosphate concentrations over a range of 2 to 60 m M. Both Langmuir and Freundlich adsorption models have been used to fit the experimental data. The results indicated the existence of different binding sites with a wide spectrum of binding energies on the calcium carbonate surface. At low adsorption densities, surface sites with highest energy are occupied first. For both aragonite and calcite, the adsorption capacity increased as the salinity of seawater decreased. The effect of salinity on the adsorption might be related to the competition of phosphate between particle surface and magnesium in seawater. These results show that calcium carbonate can act as a fast scavenger for phosphate in the water. Future works will be focused on the natural suspended matter collected in Florida Bay. The composition of suspended matter, adsorption and desorption characteristic and the effect of natural organic matters and iron oxide on the surface properties will be investigated using the suspended matter and sediments from Florida Bay.
Thank you for the more elaborated explanation, I still can’t see it affecting the discussion, because as you said there is a balance and if it were to reach zero on the water it most likely mean that there would be zero stored in the rock surfaces to.
Just more volume to take in to account if adding phosphates artificially
I will have to kindly disagree, P it’s always a limiting factor in all scenarios given by the formula, the abundance of residual P doesn’t affect N or C but C and N abundance can limit P.The point is that adsorption onto and desorption off of rock is a way that P can change without any impact on C and N. Thus, it is not correct to assume that they move up and down in any fixed ratios.
I will have to kindly disagree, P it’s always a limiting factor in all scenarios given by the formula, the abundance of residual P doesn’t affect N or C but C and N abundance can limit P.
Am not debating, am just stating that P is only a limiting factor to the other nutrients wend its zero, I’ve included GFO a few comments back, it’s a alternative to the increase of the nutrient C and N doing the same job. GFO it’s a standard procedure in reefing and the formula accounts for that.I simply stated a fact. It’s not an opinion that can be debated. Phosphate can move up or down completely independent of any changes in C or N.
Adding GFO is an example.