There is no reason to aim for the red field ratio. IMHO - if you wait long enough your tank will become the 'red field ratio'. at least it has throughout the world
Good Nitrate to Phosphate ratio for a reef tank?
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your post is exactly what I was searching for.You are right and I am doing nearly same thing,I raised my no3 to little more than 5ppm...reading test color is difficult it should be 6 or 7 on API test.On the other hand phosphate level is I think a mystery to every one people are talking of levels about 0.04 some are talking 0.1 level,Redfield chart is between 0.3 and 0.5 po4 levels which is crazy.Nevertheless I am raising on purpose to 0.08 my phosphates and noticed maybe little improvement in algae problem.
This is exactly what I have determined as well. My tank does much better (less cyano, bad gha, etc.) if my NO3 is up and PO4 down. I get more stringy algae but less of the nasty stuff, corals seem happier, more food for CUC, etc. I don’t know enough to scientifically prove it but kind of by accident that is what works for my tank. Everything just seems better with NO3 at 10-15 and PO4 .02 to .05.
OP
OP
Yes, I would use Nyos for Nitrates. Between 0-8 it’s spot on. I been keeping mine 3-8ppm lately with excellent results. I don’t like any less than 2.
Hanna Phosphorus ULR for PO4. Been keeping PO4 between 0.03 - 0.1ppm. Never more than 0.2-0.3. It can be higher, but if you don’t slowly bring it down you’ll start to grow algae which could at some point be a problem especially if you’re not out-competing it with a fuge. It also depends on the system’s age. Older tanks tolerate higher levels much better than younger ones.
Randy Holmes-Farley
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I dont really see a mechanism where raising nutrient levels can reduce algae unless it is allowing faster growth if something else that is competing with the algae for something else, like space or a trace element.
it is not the case that boosting nitrate or phosphate will, by itself, reduce the growth of an organism unless they are raised so high as to be toxic.
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Interesting discussion, let me to share a really good article with you guys. Definitely worth a read if you like the redfield ratio and more important to anyone that likes to run they’re reef at undetectable po4. Maybe this could help decide what values to aim for.
www.ncbi.nlm.nih.gov
Phosphate deficiency promotes coral bleaching and is reflected by the ultrastructure of symbiotic dinoflagellates - PMC
Enrichment of reef environments with dissolved inorganic nutrients is considered a major threat to the survival of corals living in symbiosis with dinoflagellates (Symbiodinium sp.). We argue, however, that the direct negative effects on the ...
www.ncbi.nlm.nih.gov
you speak logic,but please tell me why for a long time I had zero reading nitrates and even sometimes zero phosphates and still i had nasty growth of cyano and hair algae,ok you are going to answer that the zero is not zero since it is consumed by the algae themselves so i get zero from certain positive values,and on the other hand I know friends that have 20 mg of nitrates huge levels of phosphates and still less algae.So I am convinced that a magic ratio should exist between nitrates and phosphates.I have to mention that I am a fanatic of carbone dosing with both alcohol vodka and sugar saccharose,I monitored closely nitrates and phosphates .I never had bacterial bloom but sometimes little milky water so obviously I stop for 2 0r 3 days,sometimes I see a bloom of cyano because I think they feed on carbone also.
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Growth of algae requires lots and lots of different things. There is no reason to assume that nitrate or phosphate are limiting growth in a reef tank. Iron, manganese, light, herbivores, etc, all may keep algae in check. So to claim that more nitrate or phosphate reduces algae because some other persons tank with higher nutrients has less algae does not demonstrate that it is the higher N or P that directly deterred the algae.
OP
OP
It's been my experience that with Zero levels of N&P the ratio gets out of balance and somehow results in some weird algae growth and also affects water clarity. As soon as you bring the levels back to detectable or a little above, the water clears up and you'll notice the funky algae's will start to decline. This is only my personal experience in my tanks, so you may not have the same results. Every reef tank is different. Although I'm positive that every reef benefits from detectable levels of N&P. The only time you will see a reef thrive with zero levels is when you have a Acropora dominated system or a system with large healthy colonies that suck up the N&P and test results show zero values. We know by looking at the big colonies that the numbers aren't really zero. The only exception would be when the corals are starting to pale out. At that point it would be a good idea to dose N&P back to the system as the levels are now being depleted and the test results are indeed accurate.
I’ve seen the Redfield ratio invoked and then beat up many times on forums to talk about nuisance algae. Both are inappropriate in my opinion. I’d like to clear up a couple things about it:
1. It was determined experimentally by measuring the ratio of C, N, P in plankton from oceans around the world. Since they are the biological building blocks of most other organisms, it has been extrapolated both theoretically and experimentally to be a reasonable approximation of the ratios of the elements to many living things in the ocean.
2. As Randy and others have mentioned, it does not directly have anything to do with beneficial or detrimental levels of nutrients to have in a reef tank with regard to the growth of nuisance algae. This is obviously an important topic and what most people want to talk about here, but nothing to do with the Redfield ratio.
3. The ratio is actually important for reefkeeping though, but in less obvious ways. It helps us to understand how our nutrients levels go up or down and to what proportion with feeding and biological forms of nutrient export.
4. As was also mentioned earlier, note that when we are talking about nitrate and phosphate (as opposed to N and P) then the ratio is about 10:1, not 16:1.
5. When you feed your fish and coral, or cycle with a dead shrimp or something, you are adding nutrients approximately in this ratio, which is why we normally see much higher levels of nitrate than phosphate (about 10x). This is useful to have in the back of your mind for troubleshooting purposes, and to understand why we get funny results when we add non-biological additives. For example, when people cycle by adding ammonia (N without P or C), they get a very skewed output of high nitrate and little if any phosphate, which can be difficult to deal with later other than massive water changes or addition of phosphate and organic carbon.
6. Similarly, when you are using a biological method to export nutrients like macroalgae or carbon dosing, the nutrients are being taken up approximately in these ratios. This knowledge also helps with troubleshooting. Most notably, when one of these 3 components (C, N, P) are zero or very low, it inhibits uptake of the other nutrients by biological export methods because they are taken up in a ratio. Our tanks are thought to be relatively carbon-deficient, so when we add organic carbon in the form of carbon dosing, this kicks bacterial populations into gear since now they have the missing C in the C, N, P ratio, lowering the other 2 as they grow and get skimmed out.
7. The exact numbers of the Redfield ratio are not gospel. They are an average of a wide variety samples that were measured. There is some normal variability across types of organisms, locations, growing conditions, etc. Although this might be considered to weaken the strength of the ratio in practical use, it is actually also useful in understanding when the ratio of these gets out of balance in our tanks. Both biological additions to the tank and biological exports from the tank will have small imbalances of the ratio, which is why we find ourselves using GFO to export excess P, even though we are also exporting with macro algae for example. Similarly, this is what allows carbon dosing to work so well in most (but not all) systems.
I sincerely hope this helps some reef keepers understand when and how to use the Redfield ratio (and when not to).
1. It was determined experimentally by measuring the ratio of C, N, P in plankton from oceans around the world. Since they are the biological building blocks of most other organisms, it has been extrapolated both theoretically and experimentally to be a reasonable approximation of the ratios of the elements to many living things in the ocean.
2. As Randy and others have mentioned, it does not directly have anything to do with beneficial or detrimental levels of nutrients to have in a reef tank with regard to the growth of nuisance algae. This is obviously an important topic and what most people want to talk about here, but nothing to do with the Redfield ratio.
3. The ratio is actually important for reefkeeping though, but in less obvious ways. It helps us to understand how our nutrients levels go up or down and to what proportion with feeding and biological forms of nutrient export.
4. As was also mentioned earlier, note that when we are talking about nitrate and phosphate (as opposed to N and P) then the ratio is about 10:1, not 16:1.
5. When you feed your fish and coral, or cycle with a dead shrimp or something, you are adding nutrients approximately in this ratio, which is why we normally see much higher levels of nitrate than phosphate (about 10x). This is useful to have in the back of your mind for troubleshooting purposes, and to understand why we get funny results when we add non-biological additives. For example, when people cycle by adding ammonia (N without P or C), they get a very skewed output of high nitrate and little if any phosphate, which can be difficult to deal with later other than massive water changes or addition of phosphate and organic carbon.
6. Similarly, when you are using a biological method to export nutrients like macroalgae or carbon dosing, the nutrients are being taken up approximately in these ratios. This knowledge also helps with troubleshooting. Most notably, when one of these 3 components (C, N, P) are zero or very low, it inhibits uptake of the other nutrients by biological export methods because they are taken up in a ratio. Our tanks are thought to be relatively carbon-deficient, so when we add organic carbon in the form of carbon dosing, this kicks bacterial populations into gear since now they have the missing C in the C, N, P ratio, lowering the other 2 as they grow and get skimmed out.
7. The exact numbers of the Redfield ratio are not gospel. They are an average of a wide variety samples that were measured. There is some normal variability across types of organisms, locations, growing conditions, etc. Although this might be considered to weaken the strength of the ratio in practical use, it is actually also useful in understanding when the ratio of these gets out of balance in our tanks. Both biological additions to the tank and biological exports from the tank will have small imbalances of the ratio, which is why we find ourselves using GFO to export excess P, even though we are also exporting with macro algae for example. Similarly, this is what allows carbon dosing to work so well in most (but not all) systems.
I sincerely hope this helps some reef keepers understand when and how to use the Redfield ratio (and when not to).
Mr Mumblez
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I was hoping even though this thread is older I would post here about Hanna ultra low phosphorous checker. I recently bought it. I have been looking at it read 6 PPB which converts to .006 PPM. Seems low but I e got some red carpet algae growing like freckles on LR. I’ve added phosguard half and half with rox.8 in reactor. Seems to be keeping that red algae in check cuz it stopped spreading. Still there though so what’s the best way to remove? Without having to kill LR?
Dennis Cartier
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Some photos might help. If you are at 0.006 ppm, I would not want to go lower. You run the risk of dinoflagellates when you become to phosphate limited. If your tank is new, then it just may the natural progression of the 'uglies' while the tank achieves a balance.
Dennis
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Mr Mumblez
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Sand is super clean. I have a dragon goby that sifts all day
Mr Mumblez
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The thing I can’t understand is how to test for phosphate levels if you’ve got algae in tank. Some people say the test isn’t accurate cuz of this. So how do you get an accurate reading?
Im curious - Cyanobacteria people often say are present because of 'high nutrients' - Though I've read the low nutrient theory about dinoflagellates - I've never understood it completely - because I have had both cyanobacteria and dinoflagellates. IMHO - all of it is more complex than what we are aware. But I wondered if you had any new information about low nutrients causing dinoflagellates?
I believe that 'red carpet algae' is another name for 'cyanobacteria'. But - its hard to tell whether what is in your picture (IMO) - can you get more of a close-up? Could it be a type of corralline algae? Does it 'blow off' the rock easily? (i.e. if you use a baster - or your finger?
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I don't think the issue is that dinos thrive better in lower nutrients. That doesn't really make sense.
The issue is, IMO, that dinos thrive OK at low nutrients while other organisms that they are competing with (such as algae, but maybe other things too) do not thrive so well at low nutrients, and so the dinos win at low nutrients where the other organisms suffer.
That competition might be for a place to attach, or for other needed things like trace elements, or both.
I think this theory accounts for all the known ways to deal with dinos, and also what makes it worse.
Dennis Cartier
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I have always found that I get cyano when I have rapid rises in nitrate without an increase in phosphate. As for dinos, I have read that this can be attributed to too little phosphate, again an imbalance of nitrate to phosphate, that sets up the situation where there is ample phosphate for dinos, but insufficient for competing organisms. Basically what Randy is alluding to. Lasse has also spoke of this in some his threads. Hence my caution about trying to suppress phosphate when it is already low.
Dennis
Mr Mumblez
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This will not blow off rock, it won’t scrub off rock either. It’s slightly fuzzy looking so I figured red carpet?
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