Some articles I've read, granted it was quite a while ago now, too long ow that I think about it.. eeek I'm getting old
and it may be out of date. If I'm wrong then whatever I don't really give a toss. I am not going to have another discussion with you about this area Carson but there are more factors than influence the ionisation rate than just temperature and pH like KH something your calculator fails to take into account so it is at best a rough guide and KH is not something most people even test for. Your calculator also assumes that the equilibrium point has been reached and given the almost constant addition of ammonia it's not terrible likely that it has at any given moment. You might also want to take into consideration that the average home test has quite a reasonable error margin which makes them useless for anything more that a rough guide in a laboratory situation.
You missed the point though Carson. Water change recommendations are made on TOTAL ammonia results so putting out all this info about NH3 to NH4 to someone who is already very new to the whole process and struggling a little with what it all means is FAR from helpful. If you want to learn the ins and outs of it all them by all means do so, the internet has made it so much easier to access all the research that's been done as well as lessons on basic chemistry and biology and everything else you need but it's rarely going to be relevant on a forum like this and will likely just confuse more than it will help.
If you know all about it then fine but stop constantly trotting it out at every opportunity when it is not needed and not helpful it just makes you look like you are trying to look clever. All that knowledge is useless if you lack the wisdom to recognise when to use it.
Here's why it's all done for total ammonia.
So the average, not a chemist of mathematician, aquarium keeper can easily and quickly determine if a water change is required before all their animals suffer.
Everything available for the aquarium keeper is based around the raw test results to make it easier for people and why not when 4 days of exposure to as little as 0.019ppm NH3 at 30 degrees C will kill the average (scaled) fish and the average scaled fish has a much higher tolerance than the average axie or even than non scaled fish..... see pointless and confusing information that has no baring on anything in the original question because seriously they can't make a basic at home test that is THAT sensitive and that NH3 specific.
However over the years through the careful consideration of everything behind total ammonia at various pH's including concentrations and ionisation rates and the average pH and temperature ranges of the home aquarium and general KH values coupled with the observations of aquarium keepers has led to some very basic and very easy guides for how high is too high when it comes to ammonia in tanks.
Now I have no idea of just how much NH4 you need to kill an animal and it is considered pretty well harmless or just how long the exposure would need to be but I do know that unless you have a 100% concentration of NH4 the NH3 present would likely kill the animal long before the NH4 had a chance.
OK now I am done having this conversation with you Carson and will not be drawn into another one at the risk of being severely miss-quoted again.
SO...
Here's something that will keep you bust when you're done with the ammonia research that you will no doubt find interesting although again irrelevant in most circles
but who cares, it's interesting right
Why is a low pH no safer than a higher one? What happens to Nitrite as the pH drops? Here's a clue, Nitrous acid.
Now if I sounded condescending in you head when you read all that you may want to check your attitude and try reading it from the point of factually (to the best of my knowledge and observation) based comments from someone who is tired of having this conversation and seeing confusing information posted when it's not needed (and not just by you so chill darling) put forward to try and clear a few things up and to get across that not all information is relevant or even necessary but condescending was not how it was meant to come across but meh whatever you could always give me another negative rep if you don't like it. Whatever I really don't care, my ego's not that fragile but hey have fun with the Nitrite thing :happy:
Mere.