My thoughts on nitrite.

[brandon429]

heading over to see if that poster from nr.com wants help fixing their cycle.

we can test the outcome live time. currently booting a phone that hasn't been turned on in years that has the only cache password stored for my nr.com login not used for five years and setup with a work email from a job I no longer attend.

there's lots of barriers for me to post there I hope they agree to my test.

chances I just scared them out of reefing= 10/10

we were this close to saving someone from quitting with updated cycling science lol

 

[Jay Hemdal Verified Community Expert]

I wouldn't say it is not toxic. Even if acute or lethal it is still toxic. Found a few places for example that listed 96 hr, and 24 hr Lc50's. Which 50% of test subjects died within that time frame. Most are similar from 5 to upwards of 3000mg/L where 50% are dead in that time. That is marine fish. The safer ranges from less than .5mg/L to 15 mg/L for inverts and less than 5mg/L to 50mg/L fish in one article. Safer though still toxic. I have seen on here some that let it go to over 10mg/L. Saying one would never get to toxic levels is just false. Temperature matters cold water species are much more sensitive. To add when the temperature rises the toxicity increases to nearly double in most at usual aquarium temperatures because the fish need to take in more oxygen. It is also another unknown in common kept fish whether some fish take more nitrite via their stomach than through gills. Which would negate the effects chloride has on making nitrite absorption rates into body safer. Not to mention other variables or chemical reactions that increase toxicity as well as side effects caused even if they did not die. Some of the places I found only listed a few commonly kept fish and inverts. None were very comprehensive lists. Realistically would one want to risk a several hundred dollar fish to a possible 50% chance of survival right out of the gate without solid data? Even risk a 15% chance on top of all the other probabilities? Whether it be interfering with biological functions, increased susceptibility to disease/parasites or outright death. I would be a lot more convinced if anyone can find me Lc2's (2%) or lowest observed adverse effect levels/concentration. I would like the greatest chance of survival, long life, and good health for my pets. Until then I will personally test and control nitrite when cycling new or dealing with die off cycles.

Nitrite truly is non-toxic to marine fish except in cases where it is experimentally spiked. I cannot recall a marine system that I've ever tested that had a Nitrite-nitrogen concentration of higher than 3 mg/l. Check out Stoskopf table 21-3 page 244. The LC50 for nitrite in seawater fishes from various references ranges from 86 to 187 mg/l. The same table lists LC50 for ammonia from .3 to 1.1 mg/l NH3-N

I used to believe that nitrite was toxic to marine fish, but over the past 30 years, I've learned that it is not:

1) I've never had clinical signs of nitrite poisoning in any marine fish (production of methemoglobin).
2) I routinely alleviate nitrite toxicity in freshwater fish by the addition of NaCl
3) Randy Holmes-Farley, Ed Noga and Michael Stoskopf concur

I am not eager to extrapolate this lack of toxicity to all invertebrates, but it does seem to carry over to arthropods and mollusks.


Jay

 

[DeniableArc]

Nitrite truly is non-toxic to marine fish except in cases where it is experimentally spiked. I cannot recall a marine system that I've ever tested that had a Nitrite-nitrogen concentration of higher than 3 mg/l. Check out Stoskopf table 21-3 page 244. The LC50 for nitrite in seawater fishes from various references ranges from 86 to 187 mg/l. The same table lists LC50 for ammonia from .3 to 1.1 mg/l NH3-N

I used to believe that nitrite was toxic to marine fish, but over the past 30 years, I've learned that it is not:

1) I've never had clinical signs of nitrite poisoning in any marine fish (production of methemoglobin).
2) I routinely alleviate nitrite toxicity in freshwater fish by the addition of NaCl
3) Randy Holmes-Farley, Ed Noga and Michael Stoskopf concur

I am not eager to extrapolate this lack of toxicity to all invertebrates, but it does seem to carry over to arthropods and mollusks.


Jay

@Lasse

 

[Supa]

I’m a complete noob, just speaking from the sidelines…. But wouldn’t it be hard to perform a “controlled study” where some “test subjects” may or may not have unknown different underlying health condition or genes weaker/stronger, and any subjects that did well or didn’t in certain environment said results would be slightly compromised, and would vary durring each test round depending on whether some subjects had weaker immune or something from the start, even if you tried to compare same species from one particular source? Thanks for reading I am not a pro anything or DR or anything just like to reef and was intrigued by the thread, I also like to think nitrite is bad lol.

 

[Garf]

heading over to see if that poster from nr.com wants help fixing their cycle.

we can test the outcome live time. currently booting a phone that hasn't been turned on in years that has the only cache password stored for my nr.com login not used for five years and setup with a work email from a job I no longer attend.

there's lots of barriers for me to post there I hope they agree to my test.

While you’re there, ask him why has he overdosed the ammonia and poisoned his cycle, lol. Nitrite presence can indicate a problem, not necessarily be the problem itself.

 

[Spare time]

I think we all need to keep in mind that saying "the internet forum said x" is not scientific. Anecdotes are not studies. Observational studies by non-experts and no statistical data are useless. Stick to what the experts say (google scholar, university database, etc.), and keep it at that

 

[Jay Hemdal Verified Community Expert]

I’m a complete noob, just speaking from the sidelines…. But wouldn’t it be hard to perform a “controlled study” where some “test subjects” may or may not have unknown different underlying health condition or genes weaker/stronger, and any subjects that did well or didn’t in certain environment said results would be slightly compromised, and would vary durring each test round depending on whether some subjects had weaker immune or something from the start, even if you tried to compare same species from one particular source? Thanks for reading I am not a pro anything or DR or anything just like to reef and was intrigued by the thread, I also like to think nitrite is bad lol.

Certainly controlled studies can be helpful - that's where I got the data from that shows nitrite is non-toxic to marine fish under real world conditions. The studies I referenced used "spiked samples" where nitrite (probably as sodium nitrite) was added and then the mortality quantified. These spiked doses were 30 to 60 times HIGHER than nitrite levels seen in marine aquariums.

This mortality is often shown as 72 hour LC 50 - or, the amount of nitrite needed to kill 50% of the sample fish in 72 hours. We are of course, more interested in the LC 0. It is difficult nowadays to set up lethal environmental testing for vertebrates. I would have to petition my Institutional Animal Care and Use Committee (IACUC) for approval. The first thing they are going to ask is; are there similar studies already published? When I answer yes (see above) then my application would be denied.


Jay

 

[Supa]

Certainly controlled studies can be helpful - that's where I got the data from that shows nitrite is non-toxic to marine fish under real world conditions. The studies I referenced used "spiked samples" where nitrite (probably as sodium nitrite) was added and then the mortality quantified. These spiked doses were 30 to 60 times HIGHER than nitrite levels seen in marine aquariums.

This mortality is often shown as 72 hour LC 50 - or, the amount of nitrite needed to kill 50% of the sample fish in 72 hours. We are of course, more interested in the LC 0. It is difficult nowadays to set up lethal environmental testing for vertebrates. I would have to petition my Institutional Animal Care and Use Committee (IACUC) for approval. The first thing they are going to ask is; are there similar studies already published? When I answer yes (see above) then my application would be denied.


Jay

Yes I do agree controlled studies are great, I’m just thinking no two test subjects would ever be the same…. In theory if you ran enough test batches you would eventually land upon LC 0 a time or two and also LC50 and greater, I guess all I was trying to say is that in the event one was to see LC 0 results it would not likely happen again as the next subjects may have underlying conditions not noticeable to the eye or weaker genes which would vary the results every test. Again I don’t know much about this stuff and your opinion truly triumphs my thoughts as I am new to all of this.

 

[Jay Hemdal Verified Community Expert]

I think we all need to keep in mind that saying "the internet forum said x" is not scientific. Anecdotes are not studies. Observational studies by non-experts and no statistical data are useless. Stick to what the experts say (google scholar, university database, etc.), and keep it at that

Anecdotes are not totally useless. I knew from experience that carbon causes HLLE. I determined this as far back as 1998 through careful observation. I'd get in arguments with people all the time over it. Finally, out of frustration, a decade later, I ran my study which showed the trenchant effect of carbon on surgeonfish.

The converse is also dangerous - overextrapolation is rampant. People read a peer-reviewed paper and apply it to slightly different circumstances and it doesn't hold up. The best case of that is the "76 day survivorship of Cryptocaryon tomonts". Published by Colorni and Burgess, it was picked up by a person and widely disseminated as gospel. Trouble is, this study used survivorship in a xeric culture (no bacteria) under low temperatures. The author himself said this won't apply to actual aquariums - yet here we are, battling that misinformation.

Jay

 

[Jay Hemdal Verified Community Expert]

Yes I do agree controlled studies are great, I’m just thinking no two test subjects would ever be the same…. In theory if you ran enough test batches you would eventually land upon LC 0 a time or two and also LC50 and greater, I guess all I was trying to say is that in the event one was to see LC 0 results it would not likely happen again as the next subjects may have underlying conditions not noticeable to the eye or weaker genes which would vary the results every test. Again I don’t know much about this stuff and your opinion truly triumphs my thoughts as I am new to all of this.

There is some differences between species noted in the literature: channel catfish are very sensitive to nitrite, while bluegills are not. There can also be differences between size classes of fish - tiny fish have a much higher surface to volume ratio than do larger fish of the same species, and thus are affected by dissolved compounds differently.

However, fish of the same size and same species have pretty similar reactions. In the end, that is why they use LC50 - it picks up that variable. LC0 doesn't really tell you anything (no fish died, so you could be way below a lethal limit) and LC100 doesn't tell you much (your dose could have been a thousand times too high). The LC50 demonstrates there is an effect, but not to the point of killing all of the fish.

Jay

 

[brandon429]

Supa it sure would be hard, but imagine having literally zero data involving actual reef tanks, that'd be just as bad of a skip-to inference for things regarding reef tank cycles

it does eventually mean something when hundreds of reefs are given start dates and then we track them back six years and find happy aquarists.

we tend to overlook legitimacy of stated api nitrite data in nearly all posted reports, even though we skip over that its a stretch to say mistesting can't impact api nitrite for one reason or ten, like it does the other API kits/searches all show.


nitrite is where the doubt buck stops though...any stated level accepted without challenge. pull up nitrite posts, read what the umpires typed, see if this isn't the case.


in addition, there's a veritable army of seneye wielding chemists nowadays bent on testing cycle predictions, reporting daily in the chem forum

what that can show about ammonia ability, even in nitrite positive reefs, has been marked for pattern.



nitrite was claimed to stall ammonia processing, seneye shows across common reef tanks it never does. The longer we wait for someone to tell us that in a published study the more bottle bac will be falsely sold as stuck cycle remedy

 

[Spare time]

Anecdotes are not totally useless. I knew from experience that carbon causes HLLE. I determined this as far back as 1998 through careful observation. I'd get in arguments with people all the time over it. Finally, out of frustration, a decade later, I ran my study which showed the trenchant effect of carbon on surgeonfish.

The converse is also dangerous - overextrapolation is rampant. People read a peer-reviewed paper and apply it to slightly different circumstances and it doesn't hold up. The best case of that is the "76 day survivorship of Cryptocaryon tomonts". Published by Colorni and Burgess, it was picked up by a person and widely disseminated as gospel. Trouble is, this study used survivorship in a xeric culture (no bacteria) under low temperatures. The author himself said this won't apply to actual aquariums - yet here we are, battling that misinformation.

Jay

I wasn't saying anecdotes were useless, but observations by people untrained and that data unanalyzed is an issue as some on this sight take what they've read on forum and become "experts" by awarding themselves the title. I think anecdotes are valuable, but they do not provide absolute answers like many say. I see some on this sight instantly dismiss scholarly papers or experts because they believe keeping a fish tank = being an expert, therefore they can dismiss others. It reminds of a person saying that they have kept roosters for 10 years and every time the rooster vocalizes, the sun rises, therefore as a rooster expert I can say that roosters cause the sun to rise. Because of their "expertise," they can dismiss a study that provided data that the sun rises regardless of the rooster, and the rooster can make his noises even if the sun is not rising. I think sites like this are great for sharing what someone tried in their tank, and helping others based on their experience. The only downside of a forum like this is when people become unwilling to change their minds or claim themselves to be the authority on an issue.

 

[brandon429]

if anecdotes comprise the only data we can find to see what 100 cycling reef tanks using a given method will do, what harm is the logged pattern... without anything the guessing gets even wilder.

we at least have 100 reef examples specific to recent cycle completion that can be tracked out for disease study. that's not useless potential.

all the new entrants in the new tanks forum want to participate in any form of arrangement that seems to help their animals and investments, our hobby could benefit if more people practiced aligning things as best as possible around a given topic, using informal data sets and the feedback potential from laser clean pics and digital ammonia readouts. pop in the new tank forum and grab ten cycles to lead in a particular direction. by #75 you'll know something about that direction

people's reports and pics a year later are fine tracking indicators...excellent in fact. their own reports over being happy or sad at the outcomes counts bigtime in evals for a given claim set.

 

[Lasse]

I would love that people use the phrase not acute toxic when they refer to results from LC-50 tests. These tests say nothing about sublethal damage, stress response or death during long exposure. We do not know anything about this. And we do not know anything about other organisms response to nitrite. I maybe know that this or this organism manage - let us say - 1 ppm NO2 but during the same time that or that organism was not so successful. Was this because of the nitrite level or something else - we can´t know that

We are also talking about system that´s not fully cycled and there many starts with high concentrations of ammonia - if you start with 5 ppm NH4 (as I have seen in threads) - it means 3,9 ppm NH4 -N and fully converted to NO2 -> 3,9 NO2-N = 3,28*3,9 NO2 -> 12.8 ppm if the second step is stalled.) You read 0 ammonia and in order to verify the first step - new adding of ammonia - and nitrite can rise higher and higher if second step is stalled

I was among these that for 15 - 20 years ago was fighting for the understanding that nitrite was not as acute toxic for saltwater fish as it was for freshwater fish. We used small amounts of chloride in our freshwater aquariums if we get high nitrite levels. However - too high levels of nitrite (above 0.05 ppm IMO) indicate disturbance in the nitrification cycle and for me - a well working nitrification cycle is important for the whole system.

But this has lead to people start to think that the nitrification cycle is over when the first step has started - NH3/NH4 -> NO2. It has also lead to that many people says - do not measure nitrite. It has also lead to the believing that in a fully cycled tank - there is no nitrite. IMO - nitrite measurements is one of the best tools you have in order to understand the status of your aquarium. The NO2 -> NO3 is one of the most sensitive bacterial transformations we have in saltwater - it is very oxygen dependent, it is sensitive for antibacterial chemicals, it sensitive to excessive growth of heterotrophic bacteria and so on. With a good knowledge of your normal nitrite concentrations you can use these test as an early warning tool if the system goes south in some cases. IMO - Nitrite test are also among those tests that work good and normally rather accurate - even hobby tests.

I use a system to start my aquariums there I never get any nitrite spikes at all - I use fish as ammonia producer and amount of feed as regulating factor. I do not know if it is therefore I do not get any ugly phases or other problems when i start the aquariums. I would not panic (for my fish) if I read 1 or 2 ppm nitrite in my aquarium - instead working steady to get the nitrification process to work - but if I read that in a fishless system - I would never put a fish in that tank before I fixed the nitrification process fully out.

If you try to manage a low nitrate system - knowledge about your nitrite levels is very important because in most test - nitrite interfere with the nitrate readings.

Sincerely Lasse

 

[brandon429]

Well said. enjoyed reading that perspective.

 

[DrZoidburg]

@Jay Hemdal Stoskopf table 21-3 page 244 where do I find this I will read.

 

[DrZoidburg]

Again I would like to say sublethal effects are possible. Also it is not well studied as far as I can find so far. To add can not find very comprehensive species list. From some lists that I have found not many in the list were even commonly kept. The toxicity is obviously variable by species, environmental conditions, time of exposure, chemical reactions, salinity, temperature, and the list goes on. Its not just methemoglobinemia. What I'm proposing here also from post 1 and 12 that there can be an a huge variety of things from chronic exposure other than death. Even at low levels. To us here this is unknown, and can likely not be proven without a serious lab. By definition whether at low or high levels something that can cause cell damage is toxic. Very limited info on common search engines. Look here though some examples.
Clownfish
https://www.researchgate.net/public...icity_to_false_clownfish_Amphiprion_ocellaris You can see it is below other stated places lc50's at 344mg/L (Randys article with inactive link for species) however at a 188mg/L 50% death. As well as cell damage is occurring as low as 25mg/L according to graph. High yes but only an example for one species. Also you can see as time progress it takes substantially less NO2 to kill 50% every 24 hours.
Again here rabbitfish species
https://thefishsite.com/articles/effects-of-nitrite-exposure-on-rabbitfish You see another pattern of the amount needed being less mg/L over time to be lethal to 50%. It also mentions decreases in red blood cells at lower than lc50 levels. White blood cell changes, blood plasma increases. As well as others if you continue reading. Gill damages is noted at low levels less than 10 it is observable. Also mentions a flounder species with lc50 of 30mg/l The other chronic exposure limits would be far less than that of the rabbit fish.
Pufferfish species
https://pubmed.ncbi.nlm.nih.gov/31783303/ See over time again measured effects of enzymes, cytokines, and proteins. Though measured in millimoles it can be converted to mg/L by multiplying by molecular weight of nitrite. (46) 3mM =138 mg/L Significantly enhanced starting at 3mM. Though not mentioned there that would imply to me that these are measurable at other than biological normal levels lower than 138mg/L NO2.

Not just death but damages outside fish, enzyme changes, and immune responses. Not mentioned much also what damage is occurring inside fish other than enzymes, proteins, and responses. Clownfish example you can see in chart if gill damage goes past a certain percent it may not be reversible damage. Same thing for methemoglobinemia if it reaches a certain percent which is variable by species. Not mentioning a 6 year life of intermittent exposures. I will try to dig more on the subject. As for some inverts I have a theory why it is more toxic but that is another story.
Jay in your case you never see more than 3mg. However I have seen a few on here around 10mg. Also to add what Lasse said 12.8mg/L being possible. At 10 mg as a arbitrary standard if you will one can see damages in some species.

 

[DrZoidburg]

I’m a complete noob, just speaking from the sidelines…. But wouldn’t it be hard to perform a “controlled study” where some “test subjects” may or may not have unknown different underlying health condition or genes weaker/stronger, and any subjects that did well or didn’t in certain environment said results would be slightly compromised, and would vary durring each test round depending on whether some subjects had weaker immune or something from the start, even if you tried to compare same species from one particular source? Thanks for reading I am not a pro anything or DR or anything just like to reef and was intrigued by the thread, I also like to think nitrite is bad lol.

Very valid point. Example also wild caught vs captive bred immunities. I would venture to guess that would take many studies to make one big study. What are the chances one would have of selecting 5 near identical gene type test fish for each gene category, for each toxicity study set, and controls. If that makes sense? I imagine that would be pretty hard to do if they weren't captive bred.

 

[brandon429]

I like how easy it was for you to disregard Randy’s and Jays clear statements on the matter DZ.


you would add addenda to Randy’s article if given the edit button, no?

 

[Jay Hemdal Verified Community Expert]

@Jay Hemdal Stoskopf table 21-3 page 244 where do I find this I will read.

It is a major book that he edited, Fish Medicine. He is a aquatic veterinarian.
Jay