How useful are nitrate and phosphate test readings?

[IntrinsicReef]

I would not compare micro to macro algae in most ways - probably like comparing modern birds to dinosaurs. The two types of algae do not really act much alike even though they share some common ancestors and base characteristics.

Scrubbers work because the algae has no predators in that area - same with a fuge. True bare rock is a magnet for algae - like dry/dead rock. True live rock without corals on it is rarely bare and has coralline, fauna, matting and film bacteria, etc. that can evict dinos and hair algae before they get settled.

Algae = vacant lots and no CUC. I am glad that some of you have fish that are helpful, but I never seem to find them.

I have heard the theory that algae doesn't grow over coralline algae, but I haven't found this to be true. I've cleaned a lot of hair algae and uncovered healthy bright purple coralline on the rock underneath.

 

[Thales]

September 23rd
PO4 Hanna .64 Hach Dr890 .77
Nitrate Hanna 11.6 Hach Dr890 1.4 (x4.42) =6.18
Current P04 .5, I have not tested Nitrate since September
Photo from Nov 1, Sky on Sky Setting at 100%, shot with iphone and polyp lab gel.

I lay out my case for alage not caring about levels here



At the end of this talk there are a bunch of examples of tanks with 'high' NO3 and P04

 

[IntrinsicReef]

Algae growth has always been herbivore related to me. My previous softy tank with tangs had no visible algae but in the sump where I had a waterfall scrubber, well, algae went bonkers. I also did a submerged horizontal screen that became populated with amphipods, munching their way through it until it grew coralline.

howdy from the uk - day one

thought i would chip in and let you comment on my effort so far. Backgroung of display- 5 x 2 x 2 with 240 ltr sump containing skimmer (massively inefficient), DSB in display (silica play sand), approx 100 kgs live rock. Most corals are 7 years old and all fish but 2 of the tangs, are of...

algaescrubber.net

Yes, I agree that herbivores are the most important component of algae control. A Tang gang is essential for me in a reef tank. Urchins also consume an impressive amount of algae.

 

[jda]

I have heard the theory that algae doesn't grow over coralline algae, but I haven't found this to be true. I've cleaned a lot of hair algae and uncovered healthy bright purple coralline on the rock underneath.

I don't think that all purple is alive. I try and say actively growing coralline... most of the time. The stuff that is putting on new layers, plating and all of that never seems to have soft algae growing on it.

 

[IntrinsicReef]

I don't think that all purple is alive. I try and say actively growing coralline... most of the time. The stuff that is putting on new layers, plating and all of that never seems to have soft algae growing on it.

Gonna have to agree to disagree on this point. I have seen it too many times, and I don't think my mind can be changed on this one!

 

[Dan_P]

I agree with your philosophical digression.
For some of us, fortunately or unfortunately, the Internet is often the most easily-accessible source of information (good or bad).

Seems like there isn’t a tool to remove low quality info. Maybe AI could help on this very specific task: finding the signal in the noise.

 

[Dan_P]

The internet is perhaps the most easily accessible source for maybe data and opinions. The internet also has some information and knowledge, but this is harder to find. Books are still probably best for information and knowledge, but there are books available online.

1. Data - almost worthless, but you have to have it - too many wrongly see data as having too much value
2. Information - good, takes data, but also humans who know what they are doing
3. Knowledge - best, takes knowledge from a modicum of folks both supporting and challenging each other

What makes it so tough with reefing is that opinons and anecdotes are a lot of what we have to go with since there is so little actual good science done with regard to the hobby... so whose opinions that you choose to trust is paramount. The good thing is that the books written in the 70s, 80s and 90s are still good since biology and chemistry have not changed in our lifetimes - just ignore the specific equipment references (although some are still good).

In this case, important to see D/I/K for what they are. In a lot of these studies, what comes out of them might be knowledge for the ocean, or some lab environment, but they need to be downgraded for people with reef tanks... maybe even as far as just raw data (or maybe information if you are lucky). The best can do this - some of them post on here, so good to pay attention when they do.

Hey, very nice explanation.

 

[IntrinsicReef]

September 23rd
PO4 Hanna .64 Hach Dr890 .77
Nitrate Hanna 11.6 Hach Dr890 1.4 (x4.42) =6.18
Current P04 .5, I have not tested Nitrate since September
Photo from Nov 1, Sky on Sky Setting at 100%, shot with iphone and polyp lab gel.

I lay out my case for alage not caring about levels here



At the end of this talk there are a bunch of examples of tanks with 'high' NO3 and P04

Wow. I mention your name and phosphate, and like Beetlejuice you appear. Thank you for those links to your talks. I hadn't listened to the 2014 talk where you predict the rise of phosphate dosing. The only question I have for you is, do you have any stock market tips for me?

 

[Dan_P]

I have heard the theory that algae doesn't grow over coralline algae, but I haven't found this to be true. I've cleaned a lot of hair algae and uncovered healthy bright purple coralline on the rock underneath.

The possible missing piece to this puzzle is that healthy coralline resists epiphytic growth but stressed coralline does not, regardless the color.

 

[IntrinsicReef]

The possible missing piece to this puzzle is that healthy coralline resists epiphytic growth but stressed coralline does not, regardless the color.

I would not be surprised if coralline somewhat resisted other algae growth. I just haven't seen it make an significant impact in a situation where hair algae is prone to growing. The coralline I have seen under other algae looks like normal purple coralline with good density. I know sometimes it can look like it is dissolving. I am not sure how else to gauge coralline health.

 

[MnFish1]

TLDR: Please post a picture of your reef and include your nitrate and phosphate measurements.

-After doing thousands of tests for nitrate and phosphate over the last 20+ years on many different systems, I am still confused. I have seen tanks with undetectable NO3 and PO4 grow hair algae before my eyes. I have seen systems with 40ppm nitrate and .3ppm phosphate without a speck of algae and growing healthy coral. I just can't seem to find the pattern. New hobbyists are told to watch and manage these numbers, but we can't seem to decide what they should be. I'm beginning to think we are having the wrong conversation.

-It seems like algae and coral are utilizing these nutrients ( ammonium? some other form of phosphorus?) before they form into the compounds we are testing for. There is also an organic pool of these nutrients that we can't test for. It just seems like what we test for is a very small part of the picture.

-After many decades of hobbyists sharing test results of the world's reef tanks, I feel we should have dialed in an ideal nutrient profile. Maybe one doesn't exist. Which goes back to my point of "Why are we telling new hobbyists to concern themselves with these numbers?" Almost every time I see a person with an algae problem, the first question is "What are your nitrate and phosphate levels?" Then they get hit with a barrage of conflicting advice on what these levels should be.

-There has been talk of a "golden ratio" of nitrogen to phosphorus. Whether it is Mike Paletta observing many successful tanks at 100 to 1, or the Redfield ratio of 16-1. These ratios are often touted as responsible for specific algae/ cyano growth, as well as coral health. I have followed the 100-1 ratio for years and had success, but I have had success with other ratios. Again, I don't see a pattern (other than having more nitrogen than phosphorus in general).

-In recent years, targeting higher nutrient levels and dosing is popular for coral coloration and health. But some people find success with low nutrients and feeding their coral. Do zooxanthellae require inorganic nitrogen/phosphorus/potassium dissolved in water like terrestrial plants or can they be sated by feeding their host? Can we have low nutrient systems where the majority of nutrients are consumed by bacteria and these bacteria feed the corals? I feel like all of these are possible scenarios and are currently practiced.

-So, please post your tank and your test results. I want to see outliers like Richard Ross and whoever is the opposite low nutrient extreme. And if you know of any literature that answers these questions, please drop a link.

I (probably heresy) have seen tanks with any number of Nitrate phosphate ratios - some of which have been algae free, some having significant algae problems. So - I don't believe there is a golden ratio. However, Stability of both is important - and absolute numbers (as compared to ratios) may be important. My nitrates were running around 20 and Po4 around .05 when the last picture(s) of my tank were taken

 

[MnFish1]

BTW - when Dr. RHF sees this, he will likely indicate that the Redfield ratio does not apply and that any tying of the optimal range of one compound to another through a ratio is folly. Keep the appropriate ranges independently.

I agree.

For example a nitrate of 160 and a PO4 of 10 (of course made up numbers) have a ratio of 16:1. A nitrate of 16 and a Po4 of 1 have a ratio also of 16:1. The Redfield ratio does not even measure Nitrate and PO4.

 

[taricha]

The possible missing piece to this puzzle is that healthy coralline resists epiphytic growth but stressed coralline does not, regardless the color.

Right. And even long- dead coralline can look the same. Coralline grown on rock or glass slides still looks essentially the same even if you let it dry for weeks+.

 

[danimal1211]

A question I feel pertinent to this discussion would be whether corals receive the majority of their N&P requirements from their nutritional sources or is a significant portion gained through their own mechanisms for uptake? I feed my fish it poops and my coral eats DOCs from which it gets it N&P. Conversely I feed my fish, it poops and my corals takes in preferred Nitrogen and phosphorus from the water column.

Another example I feed my bacteria carbon, they pull Nitrogen and phosphorus from water column, then my coral eats bacteria. From this it would seem I should focus on the N&P needs of the bacteria not so much the corals.

 

[IntrinsicReef]

A question I feel pertinent to this discussion would be whether corals receive the majority of their N&P requirements from their nutritional sources or is a significant portion gained through their own mechanisms for uptake? I feed my fish it poops and my coral eats DOCs from which it gets it N&P. Conversely I feed my fish, it poops and my corals takes in preferred Nitrogen and phosphorus from the water column.

Another example I feed my bacteria carbon, they pull Nitrogen and phosphorus from water column, then my coral eats bacteria. From this it would seem I should focus on the N&P needs of the bacteria not so much the corals.

Yes. I mentioned this in my original query. I am curious if zooxanthellae needs to absorb nitrogen and phosphorus from the water column or it can fulfill those needs by sharing the nutrients their coral host eats.

 

[MnFish1]

Yes. I mentioned this in my original query. I am curious if zooxanthellae needs to absorb nitrogen and phosphorus from the water column or it can fulfill those needs by sharing the nutrients their coral host eats.

I don't know it's the same for every coral - which is why I never 'fed' my coral with special products - instead letting them glean whatever small particles they could after feeding the fish. Most SPS receive most of their energy from light/photosynthesis - so do some LPS.

 

[Ziggy17]

So I’ve read all the same stuff most have in terms of “ideal“ water parameters, and I’m guilty of buying in to them as well. But unless you have a chloromiter (sp) that costs a few grand or much more, how can we know what the water parameters actually are, given the margin of error with every test kit on the market. If the MOE is between 5-10% from most kits and you’re running tight nutes, your NO3 and PO4 could be awesome or non existent. I know we get ICP tests done, but do most write down our checker results when we pull the water for the ICP test and contrast? If they match, was it a fluke given the MOE for our home tests? It just seems that until be get super accurate home tests available to us, we are chasing a ghost (numbers), when really the livestock and nuisances should be the indicator of good water.
BTW, I’m new to the hobby and open and welcome criticism to my POV.

zig.

 

[jda]

The hosts accumulate for the zoox. They can also recycle and reuse. Hosts can also covert things for their symbiots, the most known to reefers likely being converting the unusable nitrate back into ammonium.

Even though zoox are dinos, they act differently than free living dinos.

While organic carbon dosing has shown to reduce some nitrates, nobody really posts about super huge growth changes when dosing. As such, it is not likely that developing more of the bacteria that seem to use OC helps corals out all that much. Not all corals can catch and assimilate bacteria. Not all bacteria are the kinds that corals want to absorb in their slime coats. Stonies can do it, but there is a difference between different stony types like LPS and SPS...and even with SPS an acro acts differently than a poci. I would focus on all of the different parts of the ecosystem and not just one - nobody knows if by boosting a thing with unknown value if you are harming others.

 

[IntrinsicReef]

So I’ve read all the same stuff most have in terms of “ideal“ water parameters, and I’m guilty of buying in to them as well. But unless you have a chloromiter (sp) that costs a few grand or much more, how can we know what the water parameters actually are, given the margin of error with every test kit on the market. If the MOE is between 5-10% from most kits and you’re running tight nutes, your NO3 and PO4 could be awesome or non existent. I know we get ICP tests done, but do most write down our checker results when we pull the water for the ICP test and contrast? If they match, was it a fluke given the MOE for our home tests? It just seems that until be get super accurate home tests available to us, we are chasing a ghost (numbers), when really the livestock and nuisances should be the indicator of good water.
BTW, I’m new to the hobby and open and welcome criticism to my POV.

zig.

I don't know that 5 or 10% margin of error is a reason not to test. If you are new to the hobby I would suggest testing parameters to make your own comparisons with your system health. Testing calcium and the buffer system is very important in reef tanks. A calcium reading that is 360 or 440 instead of the actual 400ppm is still very useful. Tracking trends is especially important. My questions posed on this thread are based on successful reef tanks having widely varying nitrogen and phosphorus readings. These can be 50x to even 100x in extreme examples, not a few percent difference.

 

[IntrinsicReef]

The hosts accumulate for the zoox. They can also recycle and reuse. Hosts can also covert things for their symbiots, the most known to reefers likely being converting the unusable nitrate back into ammonium.

Even though zoox are dinos, they act differently than free living dinos.

While organic carbon dosing has shown to reduce some nitrates, nobody really posts about super huge growth changes when dosing. As such, it is not likely that developing more of the bacteria that seem to use OC helps corals out all that much. Not all corals can catch and assimilate bacteria. Not all bacteria are the kinds that corals want to absorb in their slime coats. Stonies can do it, but there is a difference between different stony types like LPS and SPS...and even with SPS an acro acts differently than a poci. I would focus on all of the different parts of the ecosystem and not just one - nobody knows if by boosting a thing with unknown value if you are harming others.

Thanks. You mentioned ammonium and nitrate but what about phosphorus? I have read quite a few papers that concentrate on the dissolved nutrients that zooxanthellae utilize. It seems that in hobby talk and scientific papers that if the dissolved phosphorus drops too low, the coral suffers.

I have utilized carbon dosing in many forms over the years ( mostly bio pellets, but NoPox and vodka as well). But I am experimenting with adding vinegar to my kalkwasser along with seeding the tank with certain bacterial inoculants. The main thing I have noticed is the coral polyp extension has greatly increased, so they are definitely feeding. Color and tissue "thickness" on the Acropora has also improved. With carbon dosing and a refugium, I am headed for a low nutrient situation. It is an older system so there should be a good pool of phosphorus, but I am curious what is going to happen. It is my home experiment 150 gallon, so I am going to let it ride and see what happens!