My thoughts on nitrite.

[Lasse]

Yes, Lasse but in freshwater fish it is much, much more

This is two orders of magnitude difference.

Yes - because in freshwater - the chloride cells concentrate the NO2 levels in the blood - it is an active process through the chloride cells - and in saltwater - you have one active process in - through digestive tract and one out - the same chloride cells but in saltwater their function basically is to pump out chlorides but in a nitrite contaminated water - they have to pump out NO2 too (that have been actively pumped in by ion pumps in the digestive tract). If we look at the chloride cells - they may pump equal amount of nitrite but in two different directions if you compare fresh and saltwater. This will demand energy and in the saltwater example decreased ability to withhold osmotic homeostasis. There is reported damage on the gills both in fresh and saltwater. There can be a stress response. There is so many things that says that you should not put in fish in water with high concentration of nitrite even in saltwater.

Sincerely Lasse

 

[LRT]

Thanks for the link @Lasse
I did read and found thread super informational and educational.
Not to take away from any opposing thoughts and works here.
But was total disregard given in this thread to the thoughts, opinions and works cited from 2 of the most highly respected peers we have in Jay and Randy?

 

[Aqua Man]

I did read and found thread super informational and educational.
Not to take away from any opposing thoughts and works here.
But was total disregard given in this thread to the thoughts, opinions and works cited from 2 of the most highly respected peers we have in Jay and Randy?

How about one says it “should not” be bad. The other says it “could be” bad.

Why? Well just today I read of a new member adding 2ppm ammonia. Then more ammonia next day!! To start a new cycle. It’s very popular.

 

[Lasse]

But was total disregard given in this thread to the thoughts, opinions and works cited from 2 of the most highly respected peers we have in Jay and Randy?

I respect those two very much but that´s do not means that I can´t have other opinion than these two and defend myself in a discussion - and to make it much worse for me - I also have slight different thoughts than Hans-Werner in this thread - we can say that I´m the devil against the trinity

Sincerely Lasse

 

[Hans-Werner]

Hi Lasse,
high levels of nitrite in the digestive tract are harmful to fatal anyway, also in humans. In my opinion the ability of saltwater fish to pump nitrite ions out of the blood is rather beneficial than harmful. It may better conditions that might otherwise be lethal anyway. In clear words, in a dead fish died from cyanosis it doesn't matter much if the gills are intact still.

 

[Lasse]

high levels of nitrite in the digestive tract are harmful to fatal anyway

Yes - and that´s the reason why I fight for low threshold of nitrite in our aquariums.

In my opinion the ability of saltwater fish to pump nitrite ions out of the blood is rather beneficial than harmful

Exactly - if it was not that way - we should not have this discussion

in a dead fish died from cyanosis it doesn't matter much if the gills are intact stil

Turn it around - if a beneficial process save the life in a acute situation risk to create sublethal damage and stress that is not beneficial in the long run - it does not matter either. Especially with a problem that is very easy to solve - create an environment that is more or less free from nitrite and do not put livestock into aquariums before the whole nitrification process is completed. Instead we should be glad of the fact that if we do mistakes and nitrite rise - there is no acute situation - they will survive. However, to do this to a new rule - they will not die - therefore do not bother to create an environment with working nitrification - I never buy that.

Sincerely Lasse

 

[Hans-Werner]

create an environment that is more or less free from nitrite and do not put livestock into aquariums before the whole nitrification process is completed. Instead we should be glad of the fact that if we do mistakes and nitrite rise - there is no acute situation - they will survive. However, to do this to a new rule - they will not die - therefore do not bother to create an environment with working nitrification - I never buy that.

I think we must differentiate between the different statements.

Both, nitrification and denitrification, are not without problems in saltwater. Both processes seem to be inhibited at the stage of nitrite. My explanation is that bacteria have a similar kind of chloride/nitrite transporters as fish and they also have problems to discriminate between chloride and nitrite. In this way the chloride ion gets an competitive inhibitor to the nitrite ion. To create an environment free of nitrite, rather than trying to get the nitrification process perfectly running, which in my opinion will never work because of the competitive inhibition by chloride, create an environment virtually free of all N-ions. Stop dosing nitrate! I know you are a proponent of nitrate dosing. Even dosing nitrate may increase nitrite concentration because denitrification in part it is the perfect reverse process of nitrification and it also is inhibited at the nitrite stage by chloride. I know this from customers observing rising nitrite (and false-high nitrate) concentrations when running a nitrate reactor.

We (Tropic Marin) have products for organic carbon dosing. I observe in my everyday work with our experimental systems and I also have feedback from a German forum to one of our products that, although it never was the target of this product, it increases mating behavior and activity of fish in a positive direction. My only explanation is that it reduces the concentration of free nitrate, nitrite and ammonium ions.

This supports my approach of a virtually N-free environment for corals and fish from a very surprising direction.

 

[Lasse]

I know this from customers observing rising nitrite (and false-high nitrate) concentrations when running a nitrate reactor.

If I remember right - it was from a sulphur reactor and it known to always release nitrite in both fresh and saltwater before it starts to work properly. But even the real denitrification process can release nitrite - both in fresh and saltwater - that´s true - but also nitrite is used in the anammox process thats was first discovered in marine sediments

It is an interesting theory but I do not know if I buy it all over or at all. My real profession is freshwater fish farms and also waste water processing. IME - there is no differences between fresh and saltwater according to nitrite residues or stalling. I can easily stall a nitrification process at the second step in both fresh and saltwater with to much DOC. I have measured residue levels of nitrite in both fresh and salt water in the same concentrations (no difference between fresh and saltwater. However - it seems to be lower efficiency from both AOB and NOB in saltwater compared with freshwater. One of the explanation for aquarium and warm water aquarium could be oxygen concentrations-.

The second stage is more oxygen demanding compared with the first stage. In freshwater is the rule that it will not work properly in oxygen concentration below 5 ppm (first stage can work down to 2-3 ppm) The saturation in freshwater around 25 degree C is 8.26 ppm. The saturation in saltwater is around 20% lower at the same temperature and altitude - it means at 25 degree C - 100% saturation is around 6.6 ppm. Of experiences I know that with a good skimmer the saturation in my aquarium during night is around 80% - it means that my O2 concentration is somewhere around 5.28 ppm - very close to 5 ppm. Luck is that during photosynthesis - oxygen levels can be around 100 % saturation (and over)

If we talk about 26 degree C -> 100% saturation in saltwater is around 6.5 ppm and 80% saturation of that is 5.2 ppm.

However there is recent studies that could be of very high interest for you - here These studies have been done at around 16 degrees C and oxygen is of no concern in these temperatures - not even in saltwater.

one of our products that, although it never was the target of this product, it increases mating behavior and activity of fish in a positive direction.

Interesting to know which? Zeolite?

Sincerely Lasse

 

[Hans-Werner]

Thanks for alle the explanations, Lasse! Maybe I have to change my image of these processes a bit, we'll see ...;Bookworm

Interesting to know which? Zeolite?

No, no zeolith/klinoptilolith, it is Reef Actif, organic carbon on biopolymer basis.

 

[Hans-Werner]

So let's go back to the fish again. Why do fish take up nitrite through the intestine? In my eyes an active uptake again only makes sense if it is taken up instead of chloride. Do fish excrete and resorb hydrochloric acid in the intestines (since most fish lack a real stomach)?

Just as nitrite, nitrate is an oxidant, and even a stronger oxidant. What about nitrate? It is not taken up instead of chloride but otherwise it should not be any better.

 

[Lasse]

Maybe there is some clue here. In that article - the authors say - my bold

in the serosal solution, the equilibrium potential of NO 2 − would be approximately −120mV. This is much lower than the transepithelial potential recorded in asymmetrical in vivo conditions (−20mV; Loretz, 1995), indicating that part of the NO 2 − uptake could be by simple diffusion.

Remember the chloride cells pump out NO2 through the gills - blood content lower than ambient - diffusion?

Sincerely Lasse

 

[Aqua Man]

https://podcasts.apple.com/us/podcast/reef-news-network/id1352049776?i=1000537915508

Good interview with Dr Tim. Ten day cycle with his product and can stall if people overdosed ammonia. Great information about different species of bacteria and where they are found.

@Dan_P Dr. Tim mentions how difficult it is to actually culture bacteria.

@Lasse Dr Tim also talks about Nitrite and how it makes the fish stressed.

 

[DrZoidburg]

So let's go back to the fish again. Why do fish take up nitrite through the intestine? In my eyes an active uptake again only makes sense if it is taken up instead of chloride. Do fish excrete and resorb hydrochloric acid in the intestines (since most fish lack a real stomach)?

Just as nitrite, nitrate is an oxidant, and even a stronger oxidant. What about nitrate? It is not taken up instead of chloride but otherwise it should not be any better.

Also possible that if the physiological ph inside fish is significantly lower inside. That the equilibrium shifts to have more nitrous acid. Which is more able to permeate membranes. "The gastric pH differed considerably among treatments. Fish which had been fed only once had pH-levels in the stomach around 4.5" Further reading if fed continuously or more than a few time was as low as 2.5 ph.