I'm relying on tests to say something is toxic or not.
The normal way to test toxicity is to test acute toxicity with help of LC50 test. In short - you measure the concentration ther 50 % of the tested animals is dead after a certain time - normally LC48 and LC96. The test says nothing about which level the first organism of the test sample die - and not when the last die either. If LC50 (96 H) of a certain compound is a concentration of 2 mg/L (ppm) - the only sure answer you get is at that concentration 50 % of the tested organism is dead. As I said before - it say nothing about at which level the first organism die. It is true that LC50xx is very high for most saltwater species - we do not have the hell every freshwater aquarist have with dead fish
However - IMO - LC50 is a very blunt tool in order to evaluate a compounds real toxicity - namely it will not show any sublethal toxicity. Already back in the early 80:ties scientists who worked with ecotoxicology start to focus more on sublethal toxicity than LC50 when they talk about different compounds toxic effects in the ecosystem.
As I know - there is no scientific sublethal tests done for nitrite either in salt or fresh water - if it is please let me know.
I can´t say if nitrite is give sublethal damage to salt water fish or not. But knowing of the complex chemistry in saltwater I do not dare to stock an aquarium with living organisms in an aquarium with high levels of nitrite and will either not encourage someone to do it.
With the methods now in use - start aquarium with high doses of NH3/NH4 and dose this for more than once - it is not unlike with very high nitrite levels after a couple of days. Remember - for every 1 ppm NH4 you put in - you will have around 2.5 ppm NO2 in a new aquarium (no uptake of different organisms) if it not goes directly to nitrate. And it does not - even if people report high NO3 concentrations after a couple of days - it is only the reflection of the NO2 interference on the NO3 measure. if you have add 5 ppm (as I have seen) - we are talking about 12.5 ppm NO2 in worst case
If you use a start methode where you add very, very low amounts of NH3/NH4 a day (a fish that you feed like I describe in my 15 steps or chemical NH4 ), seed with nitrification bacteria, maybe traces of NO3 and PO4 - you never need to worry even to measure anything - the nitrification cycle will start very smooth and not hang at the second step - IME
I can´t speak about my service in different Bulletin Boards because when I did my first experiences with nitrification, fish disease and keep fishes in glass bowls there was not even any BB:s whatever. When I start to handle nitrification in my professional work - I had to learn this the hard way and through scientific literature - a PC was just a dream and we could not spell to Bulletin Board
I Europe - it is more common to measure NO2, especially in the start. This has lead too that we now know which concentrations of nitrite that´s is common in most reefs. The normal values are around 0.02 - 0,05. This measurements have been done by professional measurements by companies like Oceamo.
I can´t understand why handling nitrification in a proper way make some upset . it is not rocket science to start an aquarium the right way. There is so many parameters that we can´t control - why should we avoid to control the one that we can?
Sincerely Lasse
