Nitrite Toxicity

MnFish1

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It would not be possible for me to identify the "next" group. I seriously doubt there is one. That's because there's no value in crowd sourcing results for a process with a known and inevitable outcome.

Sorry, I didn't mean to derail this thread. I'll stop.
I don't think you need to stop. I would not say 'there is NO value' - but the value is somewhat limited IMHO, mainly because almost every one does everything slightly differently. For nearly every 'crowd sourced' result - there is another crowd that says the exact opposite. Thats when I look more to science - to help figure out which one makes the most sense. BUT - I totally agree with you having a collection of 100 threads who agree with 'one way' does not mean thats the 'correct way' (though it might be). Hope this made sense lol
 

Lasse

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Until we have standard definitions of what everyone is actually doing, I'm not sure any strong conclusions can be drawn.
According to the nitrification cycle - there is a strict scientific description NH3/NH4 ->NO2 ->NO3 When the conversion goes seamless (no NO2 build up) - the nitrification cycle is completed. If NO2 builds up the cycle is not seamless and therefore by definition nor completed

I agree that the methods are tried-and-true but does this answer the original question about nitrite toxicity specifically?
No not directly - but with the way to start aquarium that´s popular today - the risk for stalled nitrification and therefore high nitrite concentrations is much, much higher than before. The main reason is that these methods recommend to start with NH3/NH3 concentrations above 1 ppm - sometimes much higher. In the litterature about the nitrification cycle (scientific) there is rather much reports that indicate that high NH3/NH4 levels by itself block the start of the second step, hence rise in NO2 concentrations. We know that for the investigated species of fish that the acute toxic concentrations is rather high but as I have high lighted before - we do not know anything about sublethal toxicity of NO2. If people start with addition of very low addition of NH3/NH4 (either with help of a fish or addition of low addition of chemical ammonia) during 3 weeks - we do not need to bother about NO2 at all (according acute toxicity) if not a denitrification (sulphur or organic carbon based) goes very wrong

proper cycle was elimination of ammonia and nitrite as they are converted to nitrate that is removed by dilution?
Exactly
1. Do you think hypo salinity (i.e. a lower Chloride level) can make nitrite more toxic - for example in a QT tank?
2. Do you agree that a lower temperature may cause more nitrite toxicty?
I know it was directed to Randy but the question is very interesting - I will come with some - for me interesting thoughts.

In freshwater - the acute toxicity from nitrite goes down to nearly zero with only add around 80 ppm Cl ions. It will block the uptake channels in the chloride cells for NO2 uptake. The chloride cells is important in order to upheld osmotic homeostasis - to transport mainly Cl into the fish body. The salt concentration in fish is higher than in the water and therefore Cl (and other ions from other salts) tend to leave the body and water tend to come into the body. (by the way - this is the reason why freshwater fish not drink) The chloride cells have an importance in the active in transport of chloride ions. In saltwater - it is the opposite. Cl ions tend to invade the body and water tend to leave the body. Salt water fish drinks and the chloride cells transport Cl ions out from the body. IMO - no NO2 ions can go into the fish body through the chloride cells because their functions is reversed - they pump out Cl ions. However - because the fish drinks - NO2 ions can come into the fish bodies in the digestive tract. This fact make also the question about high NO3 concentrations toxicity interesting. For us humans - there is threshold values for NO3 in drinking water. The reason for this is not NO3 itself - but in the anaerobic digestive tract bacteria can do incomplete denitrification and NO2 is formed - and NO2 is then taken up into the blood stream. This means that NO3 could be more toxic (cause of it can convert into NO2 in the digestive tract) for salt water fish compared with fresh water fish (that not drink) But my experiences says nearly the opposite. The only explanation for me is once again the chloride cells and their poor ability to distinguish between CL and NO2 ions. NO2 ions will be actively pumped out (together with Cl ions). I have seen studies that indicate that it really this way and that it is so effective that the NO2 concentrations in the blood is lower than ambient water - much lower.

If this should be totally true - the acute toxicity of nitrite in saltwater should not rise before Cl concentrations in ambient water is below 80 ppm but all studies I have seen - the acute toxicity of NO2 raise with decreased salinity in concentrations very well over 80 ppm Cl ions. It is very difficult to explain but maybe the acute toxicity in saltwater depends on other things than methemoglobinemia. However - if the chloride cells should transfer out both Cl and NO2 ions against a gradient - more energy is needed compared with nitrite free water. This could - IMO - create a stress response from the fish

Sincerely Lasse
 

ReefGeezer

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I don't think you need to stop. I would not say 'there is NO value'...
You're right. I should not have spoken in absolutes. I tend to think in terms of larger tanks where the consequences of following the wrong advice can't just be "rip-cleaned" away. The "methods" that are claimed to have resulted form crowd sourcing i.e. peroxide dosing, rip-cleans, skip cycles, and etc. also just don't register in my mind as sound ways to manage a tank, particularly a larger one. Some will say I'm just old, grumpy, and not willing to accept "new science"... maybe they are correct!
 

brandon429

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don't see sand rinsing as just one way to buck the system, it provides a safety outcome as well. crash interruption and prevention for example



1/3rd of those jobs are simple home moves. they want a guaranteed way to move reefs worth twenty grand at times between homes, and that way is moving totally clean sand.

if you know of any other threads where all entrants get a safe outcome every time in home moves/ post


there are always ways to beat invasions without rip cleans

the validity needs to be evaluated solely on tank condition afterwards and not the reason a rip clean is ran. its no different than someone wanting to remove the sandbed. we're just removing it, rinsing it, putting it back. maybe across town, or the state, or maybe right back in the same spot.

we removed large portions of people's functioning biofilter there, never testing for nitrite. add that to another set of biofilter tests in large pattern where we didn't track it whatsoever. those are all displays worked, so no testing for nitrite required as its a neutral impact parameter in display tank reefing.

if someone wanted a guaranteed factual way to relocate expensive reef tanks without loss it doesn't come from any researcher it comes from a web link and a bunch of anecdotes that are now indisputable pattern. if they want to use it to beat a 4 month dinos headache, post the after pics pls
 
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LRT

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Very interesting. Ive been following both these Nitrite threads pretty closely.
From what I gather and please correct me if I'm wrong. The nitrification portion of cycle is complete when nitrite stop rising and begin to lower on its own? Feeling like this goes hand in hand with ammonia as ive observed the same exact thing?
I apologize to the hard core scientists for saying definition of cycle should be revised. I 100% agree with the definition as described by the scientific community.
Its means and methods of approach to cycling tanks that needs to clearly be re defined as by definition ive seen this process complete within first 12 hrs of setting up a new tank.
 

Duncan62

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It makes sense.

It makes sense.
I've had decent luck with a course foam that I keep soaking in a high flow area of the sump. Put it in a canisters filter for your qt. I've got some floating now. It does create an instant nitrification source. Ammonia and nitrite should not be measurable from the start. Good for a small tank. But it's also a nitrate maker big time. Lol.
 

Garf

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I've had decent luck with a course foam that I keep soaking in a high flow area of the sump. Put it in a canisters filter for your qt. I've got some floating now. It does create an instant nitrification source. Ammonia and nitrite should not be measurable from the start. Good for a small tank. But it's also a nitrate maker big time. Lol.
I’ve got a beef with the “nitrate factory” thing. How the hell can it produce more nitrate than the initial input of ammonia allows? I’ve never understood the logic behind that.
 

Duncan62

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don't see sand rinsing as just one way to buck the system, it provides a safety outcome as well. crash interruption and prevention for example



1/3rd of those jobs are simple home moves. they want a guaranteed way to move reefs worth twenty grand at times between homes, and that way is moving totally clean sand.

if you know of any other threads where all entrants get a safe outcome every time in home moves/ post


there are always ways to beat invasions without rip cleans

the validity needs to be evaluated solely on tank condition afterwards and not the reason a rip clean is ran. its no different than someone wanting to remove the sandbed. we're just removing it, rinsing it, putting it back. maybe across town, or the state, or maybe right back in the same spot.

we removed large portions of people's functioning biofilter there, never testing for nitrite. add that to another set of biofilter tests in large pattern where we didn't track it whatsoever. those are all displays worked, so no testing for nitrite required as its a neutral impact parameter in display tank reefing.

if someone wanted a guaranteed factual way to relocate expensive reef tanks without loss it doesn't come from any researcher it comes from a web link and a bunch of anecdotes that are now indisputable pattern. if they want to use it to beat a 4 month dinos headache, post the after pics pls

I’ve got a beef with the “nitrate factory” thing. How the hell can it produce more nitrate than the initial input of ammonia allows? I’ve never understood the logic behind that.
In a qt there is no means of nitrate reduction except water changes. Often I'll run a canister on a display to raise nitrate. It works. I'm not saying it increases production beyond the nutrients supplied. It simply produces with no method for reduction. BTW I got this idea years ago from a reef forum. It's not new or my creation.
 

Randy Holmes-Farley

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I’ve got a beef with the “nitrate factory” thing. How the hell can it produce more nitrate than the initial input of ammonia allows? I’ve never understood the logic behind that.

The two reasons bioballs might be termed a "nitrate factory" are collection of detritus (which is only true if that same detritus is otherwise removed from the system), and what I think is the more likely explanation:

Nitrate in the Reef Aquarium - REEFEDITION

Filters Designed To Facilitate The Nitrogen Cycle.

Filters such as trickle filters using traditional bioballs do a fine job of processing ammonia to nitrite to nitrate, but do nothing with the nitrate. It is often non-intuitive to many aquarists, but removing such a filter altogether may actually help reduce nitrate. Consequently, slowly removing them and allowing more of the nitrogen processing to take place on and in the live rock and sand can be beneficial.

It is not that any less nitrate is produced when such a filter is removed, it is a question of what happens to the nitrate after it is produced. When nitrate is produced on the surface of impermeable media such as bioballs, it mixes into the entire water column, and then has to find its way, by diffusion, to the places where it may be reduced (inside of live rock and sand, for instance).

If it is produced on the surface of live rock or sand, then the local concentration of nitrate is higher there than in the first case above, and it is more likely to diffuse into the rock and sand to be reduced to N2.

In a reef aquarium with adequate live rock, there is little use for a trickle filter, so in general they can be safely removed.
 

Randy Holmes-Farley

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Very interesting. Ive been following both these Nitrite threads pretty closely.
From what I gather and please correct me if I'm wrong. The nitrification portion of cycle is complete when nitrite stop rising and begin to lower on its own? Feeling like this goes hand in hand with ammonia as ive observed the same exact thing?
I apologize to the hard core scientists for saying definition of cycle should be revised. I 100% agree with the definition as described by the scientific community.
Its means and methods of approach to cycling tanks that needs to clearly be re defined as by definition ive seen this process complete within first 12 hrs of setting up a new tank.

I think most people would say that the nitrification is "complete" when the level of nitrite drops back to very low levels, not when it stops rising.
 

CAbercrombie

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Randy Holmes-Farley

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What about nitrates after 2 weeks and dr tims amonia and one and only mine are still high

What is the question? The nitrate is probably only reading false high from nitrite interference , but if ammonia disappeared you are good to go. :)
 

CAbercrombie

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What about nitrates after 2 weeks and dr tims amonia and one and only mine are still high

What is the question? The nitrate is probably only reading false high from nitrite interference , but if ammonia disappeared you are good to go. :)
Ammonia is at 0 i know nitrites are not toxic just wondering about nitrates both of mine have been high for over a week in a 90 gallon with 20 gallon sump even after 40% water change
 

Randy Holmes-Farley

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Ammonia is at 0 i know nitrites are not toxic just wondering about nitrates both of mine have been high for over a week in a 90 gallon with 20 gallon sump even after 40% water change

A little nitrite can read falsely as a huge amount of nitrate. One boost of ammonia to 2 ppm can only give 10 ppm nitrate. Much higher levels either require many boosts to 2 ppm, or are nitrite interference.
 

CAbercrombie

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Ammonia is at 0 i know nitrites are not toxic just wondering about nitrates both of mine have been high for over a week in a 90 gallon with 20 gallon sump even after 40% water change

A little nitrite can read falsely as a huge amount of nitrate. One boost of ammonia to 2 ppm can only give 10 ppm nitrate. Much higher levels either require many boosts to 2 ppm, or are nitrite interference.
Ok thank you, im adding fish ive been waiting on nitrites and nitrates to go down for over a week now. When i dose 2ppm amonia its gone in 24 hrs so hopefully good.
 

Randy Holmes-Farley

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Ok thank you, im adding fish ive been waiting on nitrites and nitrates to go down for over a week now. When i dose 2ppm amonia its gone in 24 hrs so hopefully good.

Yes, that’s fine.

As an example, with the Tropic Marin kit (one of the few that gives data), a nitrite value of 0.2 ppm would read as 20 ppm of nitrate when no nitrate is actually present.
 

CAbercrombie

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Ok thank you, im adding fish ive been waiting on nitrites and nitrates to go down for over a week now. When i dose 2ppm amonia its gone in 24 hrs so hopefully good.

Yes, that’s fine.

As an example, with the Tropic Marin kit (one of the few that gives data), a nitrite value of 0.2 ppm would read as 20 ppm of nitrate when no nitrate is actually present.
Thank you your knowledge and article's are really helpful. My wife has been on me you bought this tank for what to look at lol. Im gonna throw her and fish in tonight
 

Randy Holmes-Farley

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Gnop1950

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It may have been my article.

Nitrite is not toxic in marine systems and I wouldn't do anything about it.

Nitrite and the Reef Aquarium by Randy Holmes-Farley - Reefkeeping.com
http://reefkeeping.com/issues/2005-06/rhf/index.htm
Thank you. I appreciate the link, it was an interesting read (Yah, I know that makes me weird.) 😆

I would probably rephrase it the way I think you did. At least the way I took it. The normal levels of nitrite found in marine aquaria are non-toxic to marine fish, so nothing to worry about. But the absence of both Ammonia and Nitrite does indicate a complete cycle, along with rising Nitrates, correct? I know that in freshwater, 0 Ammonia and 0 Nitrites, along with increased Nitrates, indicate that the AOB and NOB are established and doing their job.

This is going to be a strange journey. While there are many similarities, there are also enormous differences between the freshwater tanks I have and my new reef tank.

I'm sure I'll have lots more questions, but I'll post them in separate threads.
 

Randy Holmes-Farley

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I think the only reason to ever measure nitrite is if one is cycling and thinks nitrite might be interfering with nitrate testing, causing a large false positive. Otherwise, it is never significant, IMO. :)
 

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