Thoughts about PO4 (particulate vs liquid)

[GARRIGA]

I understand, and I think particulate foods are the reason corals in the ocean thrive at levels of nitrate and phosphate where many folks do not see them thrive in a reef tank.

But those particulates are plankton (e.g., cyanobacteria, other bacteria, nano and picoflagellates, etc.).

https://www.jstor.org/stable/24867915

Why I mentioned just increasing food. However, if TM found evidence to suggest fish poop provides what they need then I’m all for it since that’s now one less thing to worry about in my quest to keep it simple.

 

[GARRIGA]

Hosts recycling energy and building blocks for their symbionts, and themselves, is part of the picture. Most of the rest is from particulate sources, but always organic. Most phosphorous is going to come from live (maybe some dead, but mostly live) micro organisms that get caught and assimilated in the slime coat. These come from the rocks and sand near the bases moreso than the tops where the corals have grown to form a type of shield where waves cannot break them apart. Polyp eating is not as efficient except in NPS corals.

Some of the organic micro things require light. Some of them are algae based, yet people cut that spectrum for some unknown reason. Some of them need mature live rock and sand, but people don't often want these anymore either.

You like do way more for your corals to increase the diversity and live in the ecosystem if you think that particulates matter. ...you can feed your fish more too which as long as you don't let waste products rise too much has no downside.

I’m just reflecting on the point they made using parrots pooping on a reef as a source of particulate phosphates. Not saying that even if this is valid that it would be more important than other means of obtaining required nutrients. Just thinking that if this product mimics fish poop then I’m expecting that to naturally occur in our aquariums with some bring more effective because they produce enough poop. Still not saying poop will provide. Just if it does then for some that’s already solved. We just might not be feeding enough or keeping fish counts down in fear it drives nutrients too high and something I don’t worry about because proper filtration can solve the excess

 

[Koleswrath]

These threads save me so much money.....

 

[jda]

I’m just reflecting on the point they made using parrots pooping on a reef as a source of particulate phosphates. Not saying that even if this is valid that it would be more important than other means of obtaining required nutrients. Just thinking that if this product mimics fish poop then I’m expecting that to naturally occur in our aquariums with some bring more effective because they produce enough poop. Still not saying poop will provide. Just if it does then for some that’s already solved. We just might not be feeding enough or keeping fish counts down in fear it drives nutrients too high and something I don’t worry about because proper filtration can solve the excess

Parrots would be better than sea gulls, for sure! Even that sea gull study mentions the obvious potential issue - even if bird poop had PIP, other bird waste has DIP, POP and DOP too so who is to say what dod the work? Second, sea gulls live near thriving ecosystems since food is abundant, so all of that abundance could also be what is driving the bus instead of ANY bird poop. Third, nearby reefs also thrive just as well as the ones near the birds.

When I looked at this year ago, birds seem to have p2o5 which turns into phosphoric acid in water, right? This is a DIP, IIRC, not a PIP. DIPs are known to provide phosphorous to corals. As seen yesterday when my memory failed me and I mixed up trisodium phosphate and sodium tripolyphosphate, I could be misremembering all of this, so please confirm and not trust me too much.

IMO, the bird poop thing is too much of a stretch to use it instead of a direct study that shows that PIP does nothing for coral.

 

[Randy Holmes-Farley Verified Community Expert]

Why I mentioned just increasing food. However, if TM found evidence to suggest fish poop provides what they need then I’m all for it since that’s now one less thing to worry about in my quest to keep it simple.

I don't think that is uncertain at all. It is loaded with bacteria and other useful materials.

Notice the emphasis in this article on POM, POC, PON, and no mention of inorganic particles.

Abundance, Composition and Sinking Rates of Fish Fecal Pellets in the Santa Barbara Channel - Scientific Reports

Rapidly sinking fecal pellets are an important component of the vertical flux of particulate organic matter (POM) from the surface to the ocean's interior; however, few studies have examined the role fish play in this export. We determined abundance, size, prey composition, particulate organic...

www.nature.com

Abundance, Composition and Sinking Rates of Fish Fecal Pellets in the Santa Barbara Channel
Abstract

Rapidly sinking fecal pellets are an important component of the vertical flux of particulate organic matter (POM) from the surface to the ocean's interior; however, few studies have examined the role fish play in this export. We determined abundance, size, prey composition, particulate organic carbon/nitrogen (POC/PON) and sinking rates of fecal pellets produced by a forage fish, likely the northern anchovy, in the Santa Barbara Channel. Pellet abundance ranged from 0.1–5.9 pellets m−3. POC and PON contents averaged 21.7 µg C pellet−1 and 2.7 µg N pellet−1. The sinking rate averaged 787 m d−1; thus pellets produced at the surface would reach the benthos (~500 m) in <1 day. Estimated downward flux of fish fecal POC reached a maximum of 251 mg C m−2 d−1. This is equal to or exceeds previous measurements of sediment trap POM flux and thus may transport significant amounts of repackaged surface material to depth.

 

[GARRIGA]

Parrots would be better than sea gulls, for sure! Even that sea gull study mentions the obvious potential issue - even if bird poop had PIP, other bird waste has DIP, POP and DOP too so who is to say what dod the work? Second, sea gulls live near thriving ecosystems since food is abundant, so all of that abundance could also be what is driving the bus instead of ANY bird poop. Third, nearby reefs also thrive just as well as the ones near the birds.

When I looked at this year ago, birds seem to have p2o5 which turns into phosphoric acid in water, right? This is a DIP, IIRC, not a PIP. DIPs are known to provide phosphorous to corals. As seen yesterday when my memory failed me and I mixed up trisodium phosphate and sodium tripolyphosphate, I could be misremembering all of this, so please confirm and not trust me too much.

IMO, the bird poop thing is too much of a stretch to use it instead of a direct study that shows that PIP does nothing for coral.

Talking about parrot fish not the bird. Wasn’t even thinking about the affects of non-fish poop but you raise another vector for providing phosphates as well as all other sea animals around the reefs such as turtles. Honestly not sure how this all works and wishfully hoping the poop goes to better use then just decomposing in my filter.

 

[jda]

I forgot, fish waste that your corals are not lucky enough to catch can also create/grow micro critters that your corals might be able to catch later.

The fish around the reefs that feed the other fish, algae which feeds turtles, birds, etc. was mostly what I am talking about. So much more fish waste than bird waste. The point is that the whole area is nutrient rich if there abundant life forms.

The fish waste will be used to nothing. That grey sludge/mulm that accumulates in the sump is the leftover when everything else has been used by the largest to the smallest creatures. It is inert and has no value left - many go years and years without removing it since it does not really matter. Something is getting to your fish waste and then goes back into the circle of life. I don't have an opinion about what socks and rollers do to this process, but it might be OK if they don't catch all of it.

 

[GARRIGA]

I don't think that is uncertain at all. It is loaded with bacteria and other useful materials.

Notice the emphasis in this article on POM, POC, PON, and no mention of inorganic particles.

Abundance, Composition and Sinking Rates of Fish Fecal Pellets in the Santa Barbara Channel - Scientific Reports

Rapidly sinking fecal pellets are an important component of the vertical flux of particulate organic matter (POM) from the surface to the ocean's interior; however, few studies have examined the role fish play in this export. We determined abundance, size, prey composition, particulate organic...

www.nature.com

Abundance, Composition and Sinking Rates of Fish Fecal Pellets in the Santa Barbara Channel
Abstract

Rapidly sinking fecal pellets are an important component of the vertical flux of particulate organic matter (POM) from the surface to the ocean's interior; however, few studies have examined the role fish play in this export. We determined abundance, size, prey composition, particulate organic carbon/nitrogen (POC/PON) and sinking rates of fecal pellets produced by a forage fish, likely the northern anchovy, in the Santa Barbara Channel. Pellet abundance ranged from 0.1–5.9 pellets m−3. POC and PON contents averaged 21.7 µg C pellet−1 and 2.7 µg N pellet−1. The sinking rate averaged 787 m d−1; thus pellets produced at the surface would reach the benthos (~500 m) in <1 day. Estimated downward flux of fish fecal POC reached a maximum of 251 mg C m−2 d−1. This is equal to or exceeds previous measurements of sediment trap POM flux and thus may transport significant amounts of repackaged surface material to depth.

I’ve known about marine snow for a while and recently realized we have coral deep below the depths to allow photosynthesis. Could be those deeper corals depend heavily on detritus and why I started thinking there’s substance to what TM is promoting. My research on decomposition suggests detritus isn’t the junk I thought it was and contains within elements such as calcium and magnesium for which I’ve been trying to device a means to allow full decomposition to where mulm mineralizes but perhaps that’s being utilized by corals and this product isolates the phosphorous. I’ve assumed the actual detritus would also provide other elements.

 

[GARRIGA]

I forgot, fish waste that your corals are not lucky enough to catch can also create/grow micro critters that your corals might be able to catch later.

The fish around the reefs that feed the other fish, algae which feeds turtles, birds, etc. was mostly what I am talking about. So much more fish waste than bird waste. The point is that the whole area is nutrient rich if there abundant life forms.

The fish waste will be used to nothing. That grey sludge/mulm that accumulates in the sump is the leftover when everything else has been used by the largest to the smallest creatures. It is inert and has no value left - many go years and years without removing it since it does not really matter. Something is getting to your fish waste and then goes back into the circle of life. I don't have an opinion about what socks and rollers do to this process, but it might be OK if they don't catch all of it.

I believe that mulm contains more elements that through mineralization would be released but just don’t know how to accelerate that process or find literature to make indicate how long it takes. Best I’ve found is decades and as much as a century plus but as use stated. Otherwise inert and why I don’t bother worrying about it since it might be an environment that promotes beneficial bacteria or organisms such as pods. Our hobby to preoccupied with removing everything not appealing such as GHA which on all reefs thrive. Aesthetics matter

 

[Hans-Werner]

The only places where I see this used are in spots where science has weighed in and whomever uttered the term "ahead of science" does not agree.

I mean, sometimes approaches have been confirmed by science later.

We are not talking about something that science has not just looked at yet. Science has weighed in on PIP being usable by corals and real experiments were conducted and found that it does not happen.

Please show article that describes the experiment.

 

[Hans-Werner]

I expect the phosphate in it is nearly entirely DOP (dissolved organic phosphate) and POP (particulate organic phosphate), both of which can be much more easily accessed than PIP.

I expect it may be a significant portion of POP, at least the result of a wet chemical analysis would be "POP", but a high proportion of DOP in my eyes is rather unlikely. Do you have any literature underlining this expectation?

corals use PIP directly and not incidentally get some dissolved P after it dissolved somewhere else in the system (such as in a low pH environment inside or outside of some other organism.

I was aware of the possibility that the added phosphate will take this way through the digestive tracts of other animals, beside the digestive tract of the coral itself.

In my eyes one of the possible problems some fish species have in the "clean" reef tanks (i. e. powder blue tangs) may be a deficiency of phosphate. I don't see any disadvantage of the phosphate taking the way through the digestive tracts of fish, snails, worms and other organism that may take up the particles from surfaces and may take their share. This kind of "ecosystem fertilization" was an intended side effect.

"The median phosphorus
levels of these fecal pellets were over 25 times that of any
algae taxa; this is notable as the growth of corals, reef
algae, and other organisms may be limited by these nutrients
(Howarth 1988). The high levels of phosphorus and
calcium in fecal pellets may also drive the high levels of
coprophagy we observed, since these elements cannot
solely be taken up from the environment via gills and
therefore are required from the diet (Sundell and Bjo¨rnsson
1988; Hilton 1989; Flik and Verbost 1993). Furthermore,
these micronutrients interact with one another in complex
ways based on presence and quantity within a diet, therefore
acting as important supplements (Hilton 1989). A
previous study reported higher levels of phosphorus, copper,
iron, and zinc in C. multilineata feces from St. Croix
compared to values we observed from Bonaire (Geesey
et al. 1984), suggesting that the feces of this planktivore
may be a rich source of nutrients in other areas of the
Caribbean. Broadly, these findings suggest that coprophagy
may supply an important source of micronutrients, particularly
for herbivorous fishes."

REMPEL, Hannah S., et al. Feces consumption by nominally herbivorous fishes in the Caribbean: an underappreciated source of nutrients?. Coral Reefs, 2022, 41. Jg., Nr. 2, S. 355-367.

This article is cited in my article on our homepage.

When I looked at this year ago, birds seem to have p2o5 which turns into phosphoric acid in water, right?

Sure? I mean the P2O5.

 

[tetonair]

The production of organic acids and phosphatase enzymes by these bacterial groups are responsible for the conversion of insoluble inorganic and organic phosphates into soluble forms which are available for the reef organisms. (© 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)"

Thank you for this reply Mr. Werner. I appreciate the references to the scientific studies that you included. As I mentioned, I am using Phos-Start now and the results are good!
When should I stop using Phos-Start? I see the direction to switch to Phos-Feed after 2-3mo.
Can you elaborate on why and when to switch from Phos-Start to Phos-Feed.
Thank you again.

 

[Pod_01]

That grey sludge/mulm that accumulates in the sump is the leftover when everything else has been used by the largest to the smallest creatures. It is inert and has no value left - many go years and years without removing it since it does not really matter.

Jda out of curiosity, do you clean out your sump from what ever this is? I do (once a year), but perhaps there is no reason to? Just curious. I figured it might be decaying and over time impacts the pH and water balance…
Another topic and there seems to by 100 different options on the subject.

 

[Randy Holmes-Farley Verified Community Expert]

I expect it may be a significant portion of POP, at least the result of a wet chemical analysis would be "POP", but a high proportion of DOP in my eyes is rather unlikely. Do you have any literature underlining this expectation?

There will be DOP in fish feces, as there is in all feces, but I do not know how high of a concentration it is. I've never seen anyone analyze any type of feces using oceanography definitions of dissolved vs particulate and where the P lies.

This analysis of copepod feces shows that of the organic carbon present, half is dissolved and half is particulate. Does P follow that same relationship? I do not know, but I would not assume that it is not similar.

In the article below, the feces reportedly started at 50:50, and then the DOC quickly diffused out of the pellets, leaving more and more POC.

Release of dissolved organic carbon from copepod fecal pellets in the Greenland Sea

https://www.sciencedirect.com/science/article/abs/pii/S002209819800104X

Initially the fecal pellets contained 50% of their total 14C-labeled carbon as DO14C. Of the initial DO14C pool, 86% was utilized or leached from the fecal pellets within 6 h, after which DO14C concentrations in the pellets remained low. In contrast, PO14C concentrations remained constant through the first 6 h and then slowly declined such that particulate fecal pellet carbon was lost at a rate of 0.007±0.003/h.

 

[Pod_01]

In my eyes one of the possible problems some fish species have in the "clean" reef tanks (i. e. powder blue tangs) may be a deficiency of phosphate.

Hmmm…. That is interesting. Is that the reason I see my Tomini tang eat fish poop?
When I was feeding frozen and nori he was chasing other fish to get it. I did change to pellets/ plankton and he is doing it lot less.

Fun fish regardless.

 

[Hans-Werner]

This analysis of copepod feces shows that of the organic carbon present, half is dissolved and half is particulate. Does P follow that same relationship? I do not know, but I would not assume that it is not similar.

Phosphate is different to all other macronutrients in that most of the phosphate in humans and other organisms with apatite skeletons is inorganic phosphate in the skeleton. In humans it is 85 %. Apatite is an inorganic phosphate mineral.

The proportions may be different but also crustacean skeletons and fish scales contain inorganic phosphate as apatite.

Most of the organic carbon in feces, also fish feces, is chitin, fibers and similar biopolymers that are not digested, and of course bacteria. I am a bit surprised that it is only half of the organic carbon in feces.

In phosphate I would expect it is mainly fish bones and fish scales and crustacean shells and bacteria, again. I would expect that most of the DOP is broken down to DIP and taken up during digestion. I would not expect much DOP in feces but I may be wrong.

Even in bacteria and microalgae a proportion, maybe even most, of the phosphate they contain is inorganic polyphosphates, the storage phosphates of these microorganisms. Inorganic phosphates are really omnipresent in organisms. Even for the metabolism of energy the principal compounds are ATP <---> ADP + inorganic phosphate.

In a Chinese aquaculture area in a bay most of the total dissolved phosphate was DIP and most of the particulate phosphate was PIP.

Some years ago I made several wet chemical digestion analyses for phosphates. I am not sure if I always get the best results but they usually were just 10 - 20 % reactive phosphate, 10 to 20 % DOP and 70 to 80 % inorganic polyphosphates. This was without external supply of polyphosphates, only the autochtonous polyphosphates.

I am not 100 % sure but I think organic phosphate compounds are quite stable and not as readily degraded into inorganic nutrients as many other organic compounds.

My expectation is that PIP is the most ignored phosphate supply for corals, but this still has to be proven.

 

[Hans-Werner]

Hmmm…. That is interesting. Is that the reason I see my Tomini tang eat fish poop?

Yes, like the article describes it, surgeonfish are notorious poop eaters.

 

[Hans-Werner]

When should I stop using Phos-Start? I see the direction to switch to Phos-Feed after 2-3mo.
Can you elaborate on why and when to switch from Phos-Start to Phos-Feed.

When more hair algae start to grow than you want to tolerate, then stop Phos-Start and if you still want to add phosphate change to Phos-Feed.

The reason is that in Phos-Start there is coralline algae meal which adds some nutrients and trace elements which may support algae growth, but especially in this regard really every tank is different, depending on rocks/decoration, bottom substrate, cleaning crew etc..

 

[Randy Holmes-Farley Verified Community Expert]

Phosphate is different to all other macronutrients in that most of the phosphate in humans and other organisms with apatite skeletons is inorganic phosphate in the skeleton. In humans it is 85 %. Apatite is an inorganic phosphate mineral.
...

My expectation is that PIP is the most ignored phosphate supply for corals, but this still has to be proven.

Certainly true. I am very aware of the various phosphate forms as much of my professional career was devoted to focusing on phosphate metabolism in people, and how to prevent hyperphosphatemia by binding phosphate from the human diet.

Fair enough on the PIP. I have plenty of opinions that have not been entirely proven but I still believe them.

 

[Hans-Werner]

Sure? I mean the P2O5.

Before I leave for weekend I will give the answer:

No, of course bird poop doesn't contain P2O5, because "it reacts vigorously with water and water-containing substances like wood or cotton, liberates much heat and may even cause fire due to the highly exothermic nature of such reactions. It is corrosive to metal and is very irritating – it may cause severe burns to the eye, skin, mucous membrane, and respiratory tract even at concentrations as low as 1 mg/m3.[11]" and "P2O5 content is often used by industry as proxy value for all the phosphorus oxides in a material. For example, fertilizer grade phosphoric acid can also contain various related phosphorous compounds which are also of use. All these compounds are described collectively in terms of 'P2O5 content' to allow convenient comparison of the phosphorous content of different products. Despite this, phosphorus pentoxide is not actually present in most samples as it is not stable in aqueous solutions." (Wikipedia)

In fact, to save water bird poop contains uric acid as solid, not dissolved urea like in urine. A hygroscopic phosphorus compound (besides being so reactive) would be quite counterproductive.