NO3, PO4 not the enemy

I was VERY VERY VERY lucky to have spent 3 years in the Philippines on the ocean. I learned a ton. :)

Well, that is very interesting as I also spent over 3 years in the PI and had access to pristine beach/inshore reef areas (this was back in the late 70's/early 80's). Lucky to have seen what I've seen when I saw it (Boracay when there was no electricity/night clubs and associated pollution, Palawan before all the tourists).

I can remember snorkling in the late morning and being able to see clearly 40-50 ft down, but then in the afternoon having difficulty seeing my outstretched hand in front of me due to the heavy plankton blooms. One of those 'aha' moments when you realize that food can be plentiful on the reef, just not all the time :)
 
LOL, ok my tank has 0 NO3 (or very low because of my test kit), my PO4 is I believe .1ppm. My coral are growing well, except my pipe organ it is being stubborn. The reason I don't know exactly what they are is because I don't care. In my time keeping corals it seems that these two parameters are not really important.

People seem to think NO3 and PO4 are really important and are using confirmation bias to ... well ... confirm their assessments.



I said I use high school chemistry for understanding, to the point I use hard chemistry. Is this not science? I also use some basic biology too. Am I to understand that these "lower" level sciences aren't science?



Here is an interesting fact ... in a poll from Gallup 30ish percent of people think that if you get the coof you have a 50% chance of being hospitalized. Information isn't any good without qualification and integration. Conclusions based on information that is improperly qualified is not just detrimental but destructive.

When you complete your studies and hit the real world you are going to get a taste of this. Trust me when I say this will be a re-occurring them throughout your life (it has been in mine).



I think @Charlie's Frags has laid it out. It is also to the point that I made that the business of actually reef keeping is messy and heavily empirical.



This is what you are thinking you are arguing, because you are defending your choices. The have a saying when test taking I think it is appropriate here RTFQ. :)
I do think that you are correct in most of your observations. But I don't think that people choose to remain ignorant due to the specific amounts of information available. Basic understandings of biology and chemistry IMO are a requirement for the hobby, But I also don't believe that there is a certain point that the information presented in those subjects suddenly become useless. I was also trying to make the same point about unqualified information being prevalent in the hobby. It is being able to decide what information is qualified for what topic. I won't deny that there any many tanks running 20 plus nitrates with 0.5 phosphates with large amounts of success and growth! (one of my buddies has around 120 ppm nitrates on his mixed reef) But do to information that I have observed on many occasions. I also believe that high phosphates are limiting the skeletal growth of their corals as well.
What I see is that people are not discrediting peer reviewed evidence per se, but the particular evidence presented may not align with their own experiences in their own reef aquariums. This is to be expected since how an experiment is conducted, and the environment that it is conducted in, will almost certainly differ from any randomly selected reef aquarium's environment.

So when an accepted article states that elevated phosphate causes reduced coral skeletal growth, that can be taken as truth in the context of that specific experiment. However, when a reef keeper shows that elevated phosphate levels provided good coral growth, then one should perk up and take notice. In this case, I would postulate that the addition of phosphate to a reef in the wild is adding too much phosphate to the coral's total phosphate intake since it would be ingesting more phosphate from zooplankton and/or phytoplankton than in a reef aquarium setting. Having higher phosphate levels in a reef aquarium's water column for the corals to assimilate could simply provide a similar amount of actual total phosphate intake that a coral in the wild would obtain under typical natural reef nutrient levels.
The actual consumption rates in the wild vs aquariums are definitely very large. One thing that possibly skews it is also what phosphates are bioavailable to the corals. While corals in the wild may consume much more phosphate than we know now. Each individual polyp is able to regulate prey much easier than regulating tissue absorption of different types of phosphates. This difference in assimilation strategies places the control of phosphate absorption more into the reef keepers' hands. Again, I am not discrediting tanks with high nutrients as bad. But perhaps not as optimal in the growth department due to this relation to phosphate and skeletal growth.
 
Well, that is very interesting as I also spent over 3 years in the PI and had access to pristine beach/inshore reef areas (this was back in the late 70's/early 80's). Lucky to have seen what I've seen when I saw it (Boracay when there was no electricity/night clubs and associated pollution, Palawan before all the tourists).

I can remember snorkling in the late morning and being able to see clearly 40-50 ft down, but then in the afternoon having difficulty seeing my outstretched hand in front of me due to the heavy plankton blooms. One of those 'aha' moments when you realize that food can be plentiful on the reef, just not all the time :)

I was in the North. San Fernando LU (Puro Point).

I mostly stayed near the beach. I didn't get into much more than 15 feet of water. I just thought it was incredibly kewl all of the different zones around the point. The "reefs" were much further out and much deeper.

I agree looking over the side of the banka in clear still water was crazy, almost like looking down from a sky scraper.

My take aways weren't so much about food but water flow. There was a caulerpa area and the growth was crazy. This biome was pretty interesting and for obvious reasons not really replicated in captivity. My guess is this was where the food went based on tides and currents.
 
The actual consumption rates in the wild vs aquariums are definitely very large. One thing that possibly skews it is also what phosphates are bioavailable to the corals. While corals in the wild may consume much more phosphate than we know now. Each individual polyp is able to regulate prey much easier than regulating tissue absorption of different types of phosphates. This difference in assimilation strategies places the control of phosphate absorption more into the reef keepers' hands. Again, I am not discrediting tanks with high nutrients as bad. But perhaps not as optimal in the growth department due to this relation to phosphate and skeletal growth.

Good point about bioavailability. Ease of phosphate assimilation may be the factor in why some systems have undetectable PO4, even with a good bio load/feeding, while other similar setups have consistently high PO4 levels and have to use methods of control.

One of the things that reef keepers have been hindered by in the past is not knowing total phosphate levels in their systems since we could realistically afford to only test for PO4 (inorganic phosphate, aka 'orthophosphate'). ICP testing provides that now, so that's an advancement.
 
But I don't think that people choose to remain ignorant due to the specific amounts of information available.

Who defines ignorant? This is an attitude of the young. Yes, I possessed it. I learned that it wasn't very helpful. Ignorant to me or you might be utterly wrong. You must always thing perhaps I am the one that is the ignorant one. Time and experience cure the attitude but never the reaction.

Basic understandings of biology and chemistry IMO are a requirement for the hobby,

I have known many reefers that have tanks that do not have these basic understandings. Through the qualities that I expressed before they found their version of success.

But I also don't believe that there is a certain point that the information presented in those subjects suddenly become useless.

I think diminishing returns would be a more accurate assessment.

I was also trying to make the same point about unqualified information being prevalent in the hobby. It is being able to decide what information is qualified for what topic.

Yup and I am disagreeing with your qualification. I am tying the reason to the reality of your assessment together and it isn't fitting.

I also believe that high phosphates are limiting the skeletal growth of their corals as well.

I think you have made this clear.

Here is something to think about. A hobbyist (JDA) on this board is particularly adept at growing SPS (acro). He states every 3 years he has to rip out his coral and start over from frags. This is even with heavy pruning. I don't know what his parameters are, but my thought is what does it matter if they are growing that fast what does it matter if they are not maximized. This is one of those reality situations where the study seems kind of irrelevant in the face of the reality.

I think the difference between growth in a high phosphate or low phosphate environment is pretty minimal and when you have to basically rip your tank apart every three years, seriously, what does that difference matter. I think the real reason all of this comes up is because people can't really grow coral and are struggling with answers. They have postulated that NO3 and PO4 are the culprits and mess with these parameters endlessly without considering there might be other factors involved. These people are the ones most likely to quote studies. Honestly most people that are succeeding don't need studies to prove their success. Though the may have read a bunch of studies that coalesced ideas that they may have based their success on.
 
Well, that is very interesting as I also spent over 3 years in the PI and had access to pristine beach/inshore reef areas (this was back in the late 70's/early 80's). Lucky to have seen what I've seen when I saw it (Boracay when there was no electricity/night clubs and associated pollution, Palawan before all the tourists).

I can remember snorkling in the late morning and being able to see clearly 40-50 ft down, but then in the afternoon having difficulty seeing my outstretched hand in front of me due to the heavy plankton blooms. One of those 'aha' moments when you realize that food can be plentiful on the reef, just not all the time :)
Bring up a great point. The waters around gulf reef appear almost crystal clear. But then you get in the reef with whale sharks and tangs and you can't help but get a disgusting feeling swimming in fornicated, filthy, fish egg/poop filled water. This is all happening together where I was on the reef.
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Good point about bioavailability. Ease of phosphate assimilation may be the factor in why some systems have undetectable PO4, even with a good bio load/feeding, while other similar setups have consistently high PO4 levels and have to use methods of control.

One of the things that reef keepers have been hindered by in the past is not knowing total phosphate levels in their systems since we could realistically afford to only test for PO4 (inorganic phosphate, aka 'orthophosphate'). ICP testing provides that now, so that's an advancement.
Another thing to consider is what kind of foods are also fed. Concentrations of phosphates in the ocean are low due to high consumption rates by bacteria and other organisms. But these organisms are easily captured and consumed by coral. Allowing them to self-regulate phosphate levels. But since aquarium consumption rates are seldom on par with the ocean, we are forced to have different input practices. This results in us needing higher than ocean water phosphate levels in our tanks. The only difference is the corals do not self-regulate in this regard. They are forced to adapt to the system which may take years.
Who defines ignorant? This is an attitude of the young. Yes, I possessed it. I learned that it wasn't very helpful. Ignorant to me or you might be utterly wrong. You must always thing perhaps I am the one that is the ignorant one. Time and experience cure the attitude but never the reaction.



I have known many reefers that have tanks that do not have these basic understandings. Through the qualities that I expressed before they found their version of success.



I think diminishing returns would be a more accurate assessment.



Yup and I am disagreeing with your qualification. I am tying the reason to the reality of your assessment together and it isn't fitting.



I think you have made this clear.

Here is something to think about. A hobbyist (JDA) on this board is particularly adept at growing SPS (acro). He states every 3 years he has to rip out his coral and start over from frags. This is even with heavy pruning. I don't know what his parameters are, but my thought is what does it matter if they are growing that fast what does it matter if they are not maximized. This is one of those reality situations where the study seems kind of irrelevant in the face of the reality.

I think the difference between growth in a high phosphate or low phosphate environment is pretty minimal and when you have to basically rip your tank apart every three years, seriously, what does that difference matter. I think the real reason all of this comes up is because people can't really grow coral and are struggling with answers. They have postulated that NO3 and PO4 are the culprits and mess with these parameters endlessly without considering there might be other factors involved. These people are the ones most likely to quote studies. Honestly most people that are succeeding don't need studies to prove their success. Though the may have read a bunch of studies that coalesced ideas that they may have based their success on.
I believe you have me all wrong here. I did not mean to imply you were ignorant. I was only referring to the quotation about the poll on COVID-19 and the public perception. I understand that you are very well versed in reefing and highly respect you as a person. As well as I would never resort to insulting character to get my point across.
As well as I have been enthralled with the complex discussion I have been having with you.
I also agree with many of your points, Such as the issues of NO3 and PO4 being blamed for much more than they cause. At most, they impede coral growth or affect the shown coloration. But blaming either for a complete lack of growth is wrong. JDA is also one of my favorite members of this forum. His views on lighting and nutrients I agree highly with (and his writing style is very good). Another big thing I agree on is that a good reefer does not use studies to prove success. But I believe the most successful reefers (Sprung, Randy HF, Riddle, and even JDA) utilize these studies to build their own specific reefing recipes and adapting those learned ideas into an easy-to-process book or forum post. Which now is what many reefers base their success on today.
 
Po4 literally inhibits skeletal growth. Please don't confuse random reef dudes on the internet not knowing for scientists not knowing.

https://royalsocietypublishing.org/doi/10.1098/rsos.201214
Here is the other side of the coin that high phosphates (inorganic--not to mention we can't even test organic!) do not matter (science is never settled and current science is often not accurate, check back in 5, 10, 15, 20 years, etc., not to mention reefs are not reef tanks, etc.):

 
I believe you have me all wrong here. I did not mean to imply you were ignorant. I was only referring to the quotation about the poll on COVID-19 and the public perception. I understand that you are very well versed in reefing and highly respect you as a person. As well as I would never resort to insulting character to get my point across.

Ahh the coof comment. I don't think people are per se ignorant because they are unaware of the percentages. Honestly I failed to accurately guess the correct percent too. I was simply trying to show that sometimes we think we know and we don't. Sometimes we think that science provides answers, and they do but we can misapply what they are providing answers to.

I ABSOLUTELY don't think that you are attacking me nor do I believe that you have called me or implied that I am ignorant. I think that you disagree with me. You should. You should always be skeptical of anything ANYONE says. This is an important thing to do and I think that the people that are misjudging the percentages on the coof are failing at only one thing ... being sufficiently skeptical.

As well as I have been enthralled with the complex discussion I have been having with you.

That is kewl. I didn't think that it was that complex. Having a engineer past makes me fear and respect complexity.

JDA is also one of my favorite members of this forum.

Agreed, he has totally helped me get over my bad self and put a reactor on my tank. I have a small tank and I am nervous about a reactor overwhelming. So far so good though. Though I am hoping to get some more consumption so that I can get the reactor to put out a bit more because I am running at the absolute bottom for drip rate and bubble counts. I really don't like to run my alk as high as I have it. My corals seem prefer NSW.

His views on lighting and nutrients I agree highly with

LOL both of these areas I disagree with him on, but my success isn't near his level so I have to defer.

But I believe the most successful reefers (Sprung, Randy HF, Riddle, and even JDA) utilize these studies to build their own specific reefing recipes and adapting those learned ideas into an easy-to-process book or forum post.

If you get on a research binge, look these people up and find out more about them. They are people and I have been in the hobby long enough to to see everyone except JDA for what they are ... fallible humans. :)

I do have a love for Sprung he is definitely an anomaly. He is the one that got me onto plenums and use those to this day.
 
Another thing to consider is what kind of foods are also fed. Concentrations of phosphates in the ocean are low due to high consumption rates by bacteria and other organisms. But these organisms are easily captured and consumed by coral. Allowing them to self-regulate phosphate levels. But since aquarium consumption rates are seldom on par with the ocean, we are forced to have different input practices. This results in us needing higher than ocean water phosphate levels in our tanks. The only difference is the corals do not self-regulate in this regard. They are forced to adapt to the system which may take years.

Many also feed a lot of highly concentrated processed foods these days which often cause elevated phosphate and nitrate levels. Live or frozen foods are not nearly as nutrient dense. Big 'Aha' moment when a reef aquarist grasps the concept that nitrate and phosphate can be at least be partially controlled by the type of food inputs supplied.
 
@Charlie’s Frags really helped my tank out by adding more fish, feeding more frozen food. I also have phosphate on a dosing pump now to keep it measurable. Coral coloration is the best I've ever seen. I don't have the ultra fancy acros, but the sps I do have really grow fast these days.
 
Another thing to consider is what kind of foods are also fed. Concentrations of phosphates in the ocean are low due to high consumption rates by bacteria and other organisms. But these organisms are easily captured and consumed by coral. Allowing them to self-regulate phosphate levels. But since aquarium consumption rates are seldom on par with the ocean, we are forced to have different input practices. This results in us needing higher than ocean water phosphate levels in our tanks. The only difference is the corals do not self-regulate in this regard. They are forced to adapt to the system which may take years.

I believe you have me all wrong here. I did not mean to imply you were ignorant. I was only referring to the quotation about the poll on COVID-19 and the public perception. I understand that you are very well versed in reefing and highly respect you as a person. As well as I would never resort to insulting character to get my point across.
As well as I have been enthralled with the complex discussion I have been having with you.
I also agree with many of your points, Such as the issues of NO3 and PO4 being blamed for much more than they cause. At most, they impede coral growth or affect the shown coloration. But blaming either for a complete lack of growth is wrong. JDA is also one of my favorite members of this forum. His views on lighting and nutrients I agree highly with (and his writing style is very good). Another big thing I agree on is that a good reefer does not use studies to prove success. But I believe the most successful reefers (Sprung, Randy HF, Riddle, and even JDA) utilize these studies to build their own specific reefing recipes and adapting those learned ideas into an easy-to-process book or forum post. Which now is what many reefers base their success on today.
I’ve never seen pics of Randy HF or Riddles tanks.

How do you like your hydra 64? Do your acros like it? I love my hydra 52 HD’s but can’t stand my prime 16
 
You sure are smarter than those peaky scientists!

Thus the difficulty in applying targeted scientific studies to the home reef. A controlled scientific experiment done properly will eliminate or reduce the impact any other variables that may alter the test results. That is the proper scientific process, but also makes it hard to relate those studies to a scenario that may have completely different variables.


So if Charlie has really high phosphate/nitrate and has longterm success with healthy, growing, colorful coral it seems silly to think he is doing something wrong because of some scientific study.
 
I’ve never seen pics of Randy HF or Riddles tanks.

How do you like your hydra 64? Do your acros like it? I love my hydra 52 HD’s but can’t stand my prime 16
I really liked the 64. Grew my corals well and gave me a nice blue pop that I wanted at the time. The white color rendering was a little off though and looked dull to my eyes. And there was quite a bit of shadowing. I’ve since given that setup to my mom as a birthday present (switched it to softie dominant for her) and switched to G5 radions on my new tank.
 
This tank has had me thinking a lot about theses issues lately. Brand new tank, dry rock, filled with SPS at 10 days, and absolutely thriving at 1 year in ULN by a well renowned reefer. It’s a good read, especially the people chiming in at the beginning that nutrients are too low, it will fail. Also this video is interesting food for thought too.

All of this makes me wonder if it’s really not about measured nutrients at all, but rather just inputs and consumption/export. We tend to use low nutrients as a surrogate that a tank isn’t getting fed, there are no nutrients available. But a lot of these ULNS tanks are being fed ALOT. It’s just that coral uptake and export acts to absorb/remove them so that they’re never measured and not just hanging around in the water column. Then you also have tanks thriving with high measured nutrients all the time as folks have mentioned.

It’s clear in practice both ultra low and high nutrients can be equally successful. Perhaps what’s important in either case is corals have nutrients available to them, regardless of wether they’re left to hang around in the water column or are removed. The dichotomy between low and high demonstrates there’s more to the story of coral health than just the number a test kit spits out.
 
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I really liked the 64. Grew my corals well and gave me a nice blue pop that I wanted at the time. The white color rendering was a little off though and looked dull to my eyes. And there was quite a bit of shadowing. I’ve since given that setup to my mom as a birthday present (switched it to softie dominant for her) and switched to G5 radions on my new tank.
Exactly…my Corals under the prime look very “meh”….especially in pics.
 
This tank has had me thinking a lot about theses issues lately. Brand new tank, dry rock, filled with SPS at 10 days, and absolutely thriving at 1 year in ULN by a well renowned reefer. It’s a good read, especially the people chiming in at the beginning that nutrients are too low, it will fail. Also this video is interesting food for thought too.

All of this makes me wonder if it’s really not about measured nutrients at all, but rather just inputs and consumption/export. We tend to use low nutrients as a surrogate that a tank isn’t getting fed, there are no nutrients available. But a lot of these ULNS tanks are being fed ALOT. It’s just that coral uptake and export acts to absorb/remove them so that they’re never measured and not just hanging around in the water column. Then you also have tanks thriving with high measured nutrients all the time as folks have mentioned.

It’s clear in practice both ultra low and high nutrients can be equally successful. Perhaps what’s important in either case is corals have nutrients available to them, regardless of wether they’re left to hang around in the water column or are removed. The dichotomy between low and high demonstrations there’s more to the story of coral health than just the number a test kit spits out.
This is a super common problem with measuring anything in a reef aquarium.

If you think of it like a bucket of water with a valve on it that controls how much water is coming out of the bucket it makes sense. If the amount of water coming into the bucket and the amount of water coming out match exactly then the water level in the bucket stays the same. Equivalent of measuring say 7.7 dKH alk. Let's say that the input water flow increases over the amount going out. The water level rises. Equivalent of say 9.1 dKH alk. Then let's say that the water coming in once again levels off and goes back to matching the output of bucket. This creates a weird scenario where the dKH is still 9.1 but the input and output are matched.

This is a serious issue for reef keepers and it must be kept in mind because if you try to lower the dKH you have to do it to get the level down but keep the input and output matched. This is not easy to do and it usually results in rubber banding which is seriously not stable and we know how much creatures in the ocean crave stability.
 
So my real question is how not to kill my new acro frags. I know that can't be answered, so let's get more specific.

* I have two years of NO3 and PO4 weekly test data. Should I stop wasting my time doing these tests? What can I spend that 20 minutes on instead to get better acro growth and survival?

* I feed my 120 with 9 fish (20" or so total) only two cubes per day to limit nutrient import to try to keep NO3 and PO4 under control. Should I feed more?

Thank to everyone who replied and didn't argue about "science". One would think I started a thread about covid. :)
 
* I have two years of NO3 and PO4 weekly test data. Should I stop wasting my time doing these tests? What can I spend that 20 minutes on instead to get better acro growth and survival?

I hope others chime in here so that you can get a balanced view of what people do and you can make evaluations on their success. My answer is that you should stop bothering with the nitrate and phosphate. If you are going to spend 20 minutes a day on something I would spend it sitting down and watching and thinking about your tank. It is shocking the things you come up with when you are in this meditative state.

One thing I have found is that clean up crews seem to die out rather rapidly. I have long accepted this as the nature of the beast and assumed that it was because of the age of the snail etc ... It is said incessantly that the problem is iodine and I have tried every permutation of this without any success. Through tinkering I have since learned that the problem with inverts dying is actually lack of iron. I have been dosing iron pretty heavily and my snail are absolutely doing amazing. The snails and clean up creatures can do an absolutely amazing job in dealing with algae as I am sure you are aware. Having them live and grow is pretty new to me. I keep waiting to see their foots start to "wrinkle" and then them to start falling and then watching the bristle worms do them in, but so far that has not been the case. FWIW.

* I feed my 120 with 9 fish (20" or so total) only two cubes per day to limit nutrient import to try to keep NO3 and PO4 under control. Should I feed more?

I would feed the fish until they are healthy. My wife feeds constantly and I have to get her to back off so that we don't have issues with the problems that come from obesity. It's real.

Thank to everyone who replied and didn't argue about "science". One would think I started a thread about covid

There are several contentious topics in this hobby and this is one of them. Advancing to the next level of the hobby requires solution of these contentious topics. IMO they are contentious because so many people are yet to solve them.

My build thread is wrong because I have moved. Here are current pics of my tank so you can evaluate what I am saying. Please note my 60 is now in a bin and I can't really get good pics. It is absolutely overrun with algae, but I have never seen chitons so big. :)

JPEG image 3.jpeg
 
So my real question is how not to kill my new acro frags. I know that can't be answered, so let's get more specific.

* I have two years of NO3 and PO4 weekly test data. Should I stop wasting my time doing these tests? What can I spend that 20 minutes on instead to get better acro growth and survival?

* I feed my 120 with 9 fish (20" or so total) only two cubes per day to limit nutrient import to try to keep NO3 and PO4 under control. Should I feed more?

Thank to everyone who replied and didn't argue about "science". One would think I started a thread about covid. :)

Personally, I don't think that PO4 and NO3 testing are a waste of time. Collectively, I think we might place too much emphasis on specific numbers and perhaps test too often, but looking at trends can certainly be helpful. In my current quite old system, PO4 I very rarely measure as it's always 'undetectable', but NO3 I check every month or so since I have readings and do see some fluctuation. Each system is different, so as they say 'Your mileage may vary' :)

I feed a set amount of food of various types and I have a set maintenance schedule which I've determined over time works best for my setup (no mech or chem filtration, just LR and LS). Any time I make changes I have to assess whether the amount of input (and/or the type of food supplied) and/or the output (water changes, detritus removal) needs to be modified and I do this simply by observing the coral coloration/growth and the resident algae species proliferation (or lack thereof).

As has been mentioned (but can't be overemphasized), careful and continuous observation and thoughtful assessment are essential for true success in this hobby.
 
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IF YOU HAD TO TAKE A REEFING EXAM, WOULD YOU PASS?

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    Votes: 32 45.7%
  • Not yet, but I have one that I want to buy in mind!

    Votes: 9 12.9%
  • No.

    Votes: 26 37.1%
  • Other (please explain).

    Votes: 3 4.3%
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