Are Nitrates really that important? Or is PO4 king?

[buruskeee]

I’ve been doing more reading on coral health and carbon dosing, etc, and I see mostly phosphate/phosphorus being discussed. It seems carbon dosing is primarily to deliver the PO4 to corals.

I see a lot of discussion about bottoming out PO4 which can starve corals and also contribute to dinos. Does bottoming out NO3 really cause any problems? Why do we care about a 100x NO3/PO4 ratio, or more specifically, keeping NO3 so high?

If we maintain PO4 between 0.05-0.15ppm and let NO3 fall to a low 1ppm number, what would be the issues? I ask because I always see 5-15ppm as the “range” but tanks of old used to run undetectable NO3 for decades.

I haven’t really seen a straight forward theory to this. Basically, what would take priority with testing/chasing between PO4 and NO3?

 

[Dan_P]

I haven’t really seen a straight forward theory to this. Basically, what would take priority with testing/chasing between PO4 and NO3?

Both PO4 and NO3 are worth monitoring. While the optimum PO4 concentration is still debated, a concentration between 0.03 and 0.2 ppm seems to be a safe bet for hard coral, higher for fish and soft coral. An optimum NO3 concentration seems to be between 2 and 20 ppm with hard coral, higher for fish and soft coral.. In principle, if you could tell whether the system was getting enough ammonia, maybe 0 ppm nitrate would be OK.

 

[Doctorgori]

….wish I could answer…my nitrates in all tanks are over 50, my phosphates are anywhere from .03 - .8 ..
I should be covered in algae but can’t seem to even grow chaeto ….
Following

 

[Dan_P]

….wish I could answer…my nitrates in all tanks are over 50, my phosphates are anywhere from .03 - .8 ..
I should be covered in algae but can’t seem to even grow chaeto ….
Following

Couple thoughts about Cheato.

Strong flow and algae movement especially for the free floating typs that self shade, strong lighting and sufficient trace elements (like iron) are also important for macro algae growth. Some aquarist seem to nail these requirements from the start. Those are the ones that report luxurious growth and giant balls of Cheato they need weekly trimming.

 

[GARRIGA]

Seems hobby migrating towards the understanding that coral prefer ammonium and might actually either ignore nitrates or struggle with down converting that to ammonium. Makes you wonder if in the presence of sufficient ammonium there’s any need for nitrates. Assuming that shows as a sign of adequate ammonium might not fit every tank since those overfed would likely already have sufficient of what’s really required.

Fact is I heard that yesterday from Lou at Tropic Marin on dosing carbon as to corals not wanting nitrates.

As I understand it. One study on acros concluded the need for a range on phosphates. Not aware of any other studies and seems all other comments based on anecdotal evidence. Not saying studies don’t exist. Just that I’m not aware of them and does seem as if that one study now gets applied to every Stick, LPS and softy. Richard Ross however doesn’t agree. His anecdotal experience suggests otherwise and have heard others mention it depends on what Stick and why I’m thinking there’s no conclusive rule as to what is tolerated and fact what we test isn’t what nature uses being another problematic concern with trying to set rules based on strict ranges or assumptions.

 

[Doctorgori]

why I’m thinking there’s no conclusive rule as to what is tolerated and fact what we test isn’t what nature uses being another problematic concern with trying to set rules based on strict ranges or assumptions.

agree, something else is amiss or our understanding is incomplete at best …
FWIW I watched the same TM youtube vid yesterday and agree that Redfield ratio thing is poo poo

 

[Dburr1014]

This is my old 75g. It's been broken down and all contents went into my 150g.

I was dosing nitrate but I stopped. That's was in April last year. Then started dosing ammonium chloride but was getting cyano mats. Stopped that too.

Nitrate in the 150 are trending down as things are growing. I will test later when I get home today. I feed my fish 4 times a day.

 

[SDchris]

IMO the difference comes when talking about N & P cycles.
I hate the nitrogen cycle. It solves a problem that's not a problem to start with. But even worse, it implies by it's definition, more filter is better. Filter being rock, sand, algae....
The phosphorus cycle tends towards; it's not about quantity, but how you manage it.

 

[Randy Holmes-Farley]

. It seems carbon dosing is primarily to deliver the PO4 to corals.

Carbon dosing reduces nitrate considerably and perhaps phosphate a small amount. It is not used to deliver phosphate unless you mean highly specialized organics containing phosphate, or mean the consumption of bacteria by corals.

 

[GARRIGA]

agree, something else is amiss or our understanding is incomplete at best …
FWIW I watched the same TM youtube vid yesterday and agree that Redfield ratio thing is poo poo

Based on my experience I will say this about ratios. Post cycle last build my nitrates would not drop regardless how much carbon I overdosed. Read up on Redfield and added phosphates based on that ratio. Nitrates had originally been over 160 ppm because I stress tested my biological filter by increasing the ammonium dose and wasn't until adding phosphates that nitrates finally bottomed out although now I had phosphates which implies I dosed too much. No water changes. Conclusion post reading up on Redfield and my experience, there's likely not an exact ratio but bacteria does require phosphates to process nitrates. Latter should have been obvious but I learn as I go and now ignore Redfield other than knowing life requires more than we likely grasp and why I don't stress when assumed ranges aren't aligned perfectly. Rather solve what happens and find a solution through trial and error then adhere to current norms knowing all to well how that's aged past 40 plus years keeping some form of life in a box. Having an open mind and questioning norms the only way I'll advance my knowledge.

Lou himself admitted he now has a different understanding of how to suggest using his own product and I expect that with time that will change, as well. Hobbyist of all types tend to learn something new and accepted by the community and make it gospel thereby ignoring all other logic and adhering to this one belief at the expense of possibly acquiring new knowledge until something else becomes universally accepted and that now becomes the new and only path. Although entertaining. Does make the one questioning norms seem odd

 

[rtparty]

Nitrates aren’t important. They are simply the measure of how much ammonia is being converted before it is utilized. Organisms in our systems prefer ammonia. Having some nitrates indicates we have just enough ammonia going in to feed everything but aren’t overdoing it.

 

[Northern Flicker]

Seems hobby migrating towards the understanding that coral prefer ammonium and might actually either ignore nitrates or struggle with down converting that to ammonium. Makes you wonder if in the presence of sufficient ammonium there’s any need for nitrates. Assuming that shows as a sign of adequate ammonium might not fit every tank since those overfed would likely already have sufficient of what’s really required.

Fact is I heard that yesterday from Lou at Tropic Marin on dosing carbon as to corals not wanting nitrates.

As I understand it. One study on acros concluded the need for a range on phosphates. Not aware of any other studies and seems all other comments based on anecdotal evidence. Not saying studies don’t exist. Just that I’m not aware of them and does seem as if that one study now gets applied to every sticks, LPS and softy. Richard Ross however doesn’t agree. His anecdotal experience suggests otherwise and have heard others mention it depends on what Stick and why I’m thinking there’s no conclusive rule as to what is tolerated and fact what we test isn’t what nature uses being another problematic concern with trying to set rules based on strict ranges or assumptions.

I would refer to this post:

Carbon dosing benefits explanation. Great video

www.reef2reef.com

Nitrates are an insurance policy, but ammonia is preferred. Randy links a couple good reads in that post, and there is a whole discussion on Lou's comments from that video.

 

[Northern Flicker]

Nitrates aren’t important. They are simply the measure of how much ammonia is being converted before it is utilized. Organisms in our systems prefer ammonia. Having some nitrates indicates we have just enough ammonia going in to feed everything but aren’t overdoing it.

Same link as quoted above:

Carbon dosing benefits explanation. Great video

www.reef2reef.com

Personally I found my acros coloured up significantly after I began to dose nitrates - these nitrates were never in an ammonia form. Anecdotal but also aligns with Randy's comments in the linked post above.

 

[Reefahholic]

Phosphate is no doubt the King, but nitrate is definitely important.

 

[Lavey29]

Let your nitrates bottom out and your corals will show you clearly if they are important or not over the subsequent couple months.

 

[rtparty]

Same link as quoted above:

Carbon dosing benefits explanation. Great video

www.reef2reef.com

Personally I found my acros coloured up significantly after I began to dose nitrates - these nitrates were never in an ammonia form. Anecdotal but also aligns with Randy's comments in the linked post above.

Corals convert nitrates back into nitrites or ammonia for consumption. So it does work to dose them. It just easier and better to dose ammonia to begin with

 

[Lavey29]

Nitrates aren’t important. They are simply the measure of how much ammonia is being converted before it is utilized. Organisms in our systems prefer ammonia. Having some nitrates indicates we have just enough ammonia going in to feed everything but aren’t overdoing it.

While in theory you are correct why are there countless threads on here with people that have struggling or dying corals and a common denominator of low or bottomed out nitrates particularly with LPS tanks? I have found that maintaining a ratio of 100:1 nitrates to phosphate is very effective for coral health and growth. I am not able to always maintain this ratio due to my phosphate level which is currently. 39 and nitrates at 20 but am generally close to the ratio. This provides substantial growth and color to all my corals.

 

[rtparty]

Same link as quoted above:

Carbon dosing benefits explanation. Great video

www.reef2reef.com

Personally I found my acros coloured up significantly after I began to dose nitrates - these nitrates were never in an ammonia form. Anecdotal but also aligns with Randy's comments in the linked post above.

Here is an amazing thread on nitrates and phosphates. Hans Werner spells it out clear as day

NP Plus - Phosphate / Nitrate ratio

According to previous threads on NP Plus, I am suppose to test phosphate only because nitrate is expected to remain 0 while using NP Plus. I did not know that at first so I kept dumping NP Plus and testing my nitrate. I finally got a Hanna Phosphate test kit and it is reading 0.39 for...

www.reef2reef.com

 

[Dburr1014]

Here is an amazing thread on nitrates and phosphates. Hans Werner spells it out clear as day

NP Plus - Phosphate / Nitrate ratio

According to previous threads on NP Plus, I am suppose to test phosphate only because nitrate is expected to remain 0 while using NP Plus. I did not know that at first so I kept dumping NP Plus and testing my nitrate. I finally got a Hanna Phosphate test kit and it is reading 0.39 for...

www.reef2reef.com

That is a good read and makes much sense in my head. Thanks!

 

[GARRIGA]

I would refer to this post:

Carbon dosing benefits explanation. Great video

www.reef2reef.com

Nitrates are an insurance policy, but ammonia is preferred. Randy links a couple good reads in that post, and there is a whole discussion on Lou's comments from that video.

My research since the 70s leads my thought process and with that I don't believe one needs to read nitrates in an environment where organism benefit directly from ammonium. Ran these tests in FW where plants fed by fish population waste never showed any readings of nitrates or nitrites or ammonium. I believe that if one is reading nitrates then either denitrification is lacking where nitrification exists or organisms dependent on ammonium are being overfed thereby some of that ammonium processed by nitrification. I'm going to aim for zero nutrients and overfeed my inhabitants. Rely on photosynthetic organisms and an oversized biological media bed to process the rest. Might dose carbon as I understand that the bacterial bloom from that feeds the corals.